:: LPSPACE2 semantic presentation begin theorem Th1: :: LPSPACE2:1 for m, n being positive real number st (1 / m) + (1 / n) = 1 holds m > 1 proof let m, n be positive real number ; ::_thesis: ( (1 / m) + (1 / n) = 1 implies m > 1 ) assume (1 / m) + (1 / n) = 1 ; ::_thesis: m > 1 then A1: 1 / n = 1 - (1 / m) ; assume m <= 1 ; ::_thesis: contradiction then 1 <= 1 / m by XREAL_1:181; hence contradiction by A1, XREAL_1:47; ::_thesis: verum end; theorem Th2: :: LPSPACE2:2 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for A being Element of S for f being PartFunc of X,ExtREAL st A = dom f & f is_measurable_on A & f is nonnegative holds ( Integral (M,f) in REAL iff f is_integrable_on M ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for A being Element of S for f being PartFunc of X,ExtREAL st A = dom f & f is_measurable_on A & f is nonnegative holds ( Integral (M,f) in REAL iff f is_integrable_on M ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for A being Element of S for f being PartFunc of X,ExtREAL st A = dom f & f is_measurable_on A & f is nonnegative holds ( Integral (M,f) in REAL iff f is_integrable_on M ) let M be sigma_Measure of S; ::_thesis: for A being Element of S for f being PartFunc of X,ExtREAL st A = dom f & f is_measurable_on A & f is nonnegative holds ( Integral (M,f) in REAL iff f is_integrable_on M ) let A be Element of S; ::_thesis: for f being PartFunc of X,ExtREAL st A = dom f & f is_measurable_on A & f is nonnegative holds ( Integral (M,f) in REAL iff f is_integrable_on M ) let f be PartFunc of X,ExtREAL; ::_thesis: ( A = dom f & f is_measurable_on A & f is nonnegative implies ( Integral (M,f) in REAL iff f is_integrable_on M ) ) assume A1: ( A = dom f & f is_measurable_on A & f is nonnegative ) ; ::_thesis: ( Integral (M,f) in REAL iff f is_integrable_on M ) A2: now__::_thesis:_(_f_is_integrable_on_M_implies_Integral_(M,f)_in_REAL_) assume f is_integrable_on M ; ::_thesis: Integral (M,f) in REAL then ( -infty < Integral (M,f) & Integral (M,f) < +infty ) by MESFUNC5:96; hence Integral (M,f) in REAL by XXREAL_0:14; ::_thesis: verum end; now__::_thesis:_(_Integral_(M,f)_in_REAL_implies_f_is_integrable_on_M_) assume A3: Integral (M,f) in REAL ; ::_thesis: f is_integrable_on M A4: ( dom (max- f) = A & max- f is_measurable_on A ) by A1, MESFUNC2:26, MESFUNC2:def_3; A5: ( dom (max+ f) = A & max+ f is_measurable_on A ) by A1, MESFUNC2:25, MESFUNC2:def_2; for x being Element of X holds 0 <= (max+ f) . x by MESFUNC2:12; then max+ f is nonnegative by SUPINF_2:39; then A6: Integral (M,(max+ f)) = integral+ (M,(max+ f)) by A5, MESFUNC5:88; A7: for x being Element of X st x in dom f holds (max+ f) . x = f . x proof let x be Element of X; ::_thesis: ( x in dom f implies (max+ f) . x = f . x ) A8: f . x >= 0 by A1, SUPINF_2:39; assume x in dom f ; ::_thesis: (max+ f) . x = f . x then (max+ f) . x = max ((f . x),0) by A1, A5, MESFUNC2:def_2; hence (max+ f) . x = f . x by A8, XXREAL_0:def_10; ::_thesis: verum end; then max+ f = f by A1, A5, PARTFUN1:5; then A9: Integral (M,(max+ f)) < +infty by A3, XXREAL_0:9; for x being Element of X holds 0 <= (max- f) . x by MESFUNC2:13; then max- f is nonnegative by SUPINF_2:39; then A10: Integral (M,(max- f)) = integral+ (M,(max- f)) by A4, MESFUNC5:88; for x being Element of X st x in dom (max- f) holds 0 = (max- f) . x proof let x be Element of X; ::_thesis: ( x in dom (max- f) implies 0 = (max- f) . x ) assume x in dom (max- f) ; ::_thesis: 0 = (max- f) . x (max+ f) . x = f . x by A1, A5, A7, PARTFUN1:5; hence 0 = (max- f) . x by MESFUNC2:19; ::_thesis: verum end; then Integral (M,(max- f)) = 0 by A4, LPSPACE1:22; hence f is_integrable_on M by A1, A6, A9, A10, MESFUNC5:def_17; ::_thesis: verum end; hence ( Integral (M,f) in REAL iff f is_integrable_on M ) by A2; ::_thesis: verum end; definition let r be real number ; attrr is geq_than_1 means :Def1: :: LPSPACE2:def 1 1 <= r; end; :: deftheorem Def1 defines geq_than_1 LPSPACE2:def_1_:_ for r being real number holds ( r is geq_than_1 iff 1 <= r ); registration cluster real geq_than_1 -> positive real for set ; coherence for b1 being real number st b1 is geq_than_1 holds b1 is positive proof let r be real number ; ::_thesis: ( r is geq_than_1 implies r is positive ) assume 1 <= r ; :: according to LPSPACE2:def_1 ::_thesis: r is positive hence r is positive ; ::_thesis: verum end; end; registration cluster ext-real V38() real geq_than_1 for Element of REAL ; existence ex b1 being Real st b1 is geq_than_1 proof take 1 ; ::_thesis: 1 is geq_than_1 thus 1 is geq_than_1 by Def1; ::_thesis: verum end; end; theorem Th3: :: LPSPACE2:3 for a, b, p being Real st 0 < p & 0 <= a & a < b holds a to_power p < b to_power p proof let a, b, p be Real; ::_thesis: ( 0 < p & 0 <= a & a < b implies a to_power p < b to_power p ) assume A1: ( 0 < p & 0 <= a & a < b ) ; ::_thesis: a to_power p < b to_power p now__::_thesis:_(_a_=_0_implies_a_to_power_p_<_b_to_power_p_) assume a = 0 ; ::_thesis: a to_power p < b to_power p then a to_power p = 0 by A1, POWER:def_2; hence a to_power p < b to_power p by A1, POWER:34; ::_thesis: verum end; hence a to_power p < b to_power p by A1, POWER:37; ::_thesis: verum end; theorem Th4: :: LPSPACE2:4 for a, b being Real st a >= 0 & b > 0 holds a to_power b >= 0 proof let a, b be Real; ::_thesis: ( a >= 0 & b > 0 implies a to_power b >= 0 ) assume A1: a >= 0 ; ::_thesis: ( not b > 0 or a to_power b >= 0 ) assume b > 0 ; ::_thesis: a to_power b >= 0 then ( a = 0 implies a to_power b >= 0 ) by POWER:def_2; hence a to_power b >= 0 by A1, POWER:34; ::_thesis: verum end; theorem Th5: :: LPSPACE2:5 for a, b, c being Real st a >= 0 & b >= 0 & c > 0 holds (a * b) to_power c = (a to_power c) * (b to_power c) proof let a, b, c be Real; ::_thesis: ( a >= 0 & b >= 0 & c > 0 implies (a * b) to_power c = (a to_power c) * (b to_power c) ) assume that A1: ( a >= 0 & b >= 0 ) and A2: c > 0 ; ::_thesis: (a * b) to_power c = (a to_power c) * (b to_power c) now__::_thesis:_(_(_a_=_0_or_b_=_0_)_implies_(a_*_b)_to_power_c_=_(a_to_power_c)_*_(b_to_power_c)_) assume A3: ( a = 0 or b = 0 ) ; ::_thesis: (a * b) to_power c = (a to_power c) * (b to_power c) then (a * b) to_power c = 0 by A2, POWER:def_2; hence (a * b) to_power c = (a to_power c) * (b to_power c) by A3; ::_thesis: verum end; hence (a * b) to_power c = (a to_power c) * (b to_power c) by A1, POWER:30; ::_thesis: verum end; theorem Th6: :: LPSPACE2:6 for X being non empty set for a, b being Real for f being PartFunc of X,REAL st f is nonnegative & a > 0 & b > 0 holds (f to_power a) to_power b = f to_power (a * b) proof let X be non empty set ; ::_thesis: for a, b being Real for f being PartFunc of X,REAL st f is nonnegative & a > 0 & b > 0 holds (f to_power a) to_power b = f to_power (a * b) let a, b be Real; ::_thesis: for f being PartFunc of X,REAL st f is nonnegative & a > 0 & b > 0 holds (f to_power a) to_power b = f to_power (a * b) let f be PartFunc of X,REAL; ::_thesis: ( f is nonnegative & a > 0 & b > 0 implies (f to_power a) to_power b = f to_power (a * b) ) assume A1: ( f is nonnegative & a > 0 & b > 0 ) ; ::_thesis: (f to_power a) to_power b = f to_power (a * b) A2: ( dom (f to_power a) = dom f & dom ((f to_power a) to_power b) = dom (f to_power a) & dom (f to_power (a * b)) = dom f ) by MESFUN6C:def_4; for x being set st x in dom ((f to_power a) to_power b) holds ((f to_power a) to_power b) . x = (f to_power (a * b)) . x proof let x be set ; ::_thesis: ( x in dom ((f to_power a) to_power b) implies ((f to_power a) to_power b) . x = (f to_power (a * b)) . x ) assume A3: x in dom ((f to_power a) to_power b) ; ::_thesis: ((f to_power a) to_power b) . x = (f to_power (a * b)) . x then A4: ((f to_power a) to_power b) . x = ((f to_power a) . x) to_power b by MESFUN6C:def_4 .= ((f . x) to_power a) to_power b by A2, A3, MESFUN6C:def_4 ; A5: (f to_power (a * b)) . x = (f . x) to_power (a * b) by A2, A3, MESFUN6C:def_4; then A6: ( f . x > 0 implies ((f to_power a) to_power b) . x = (f to_power (a * b)) . x ) by A4, POWER:33; now__::_thesis:_(_f_._x_=_0_implies_((f_to_power_a)_to_power_b)_._x_=_(f_to_power_(a_*_b))_._x_) assume A7: f . x = 0 ; ::_thesis: ((f to_power a) to_power b) . x = (f to_power (a * b)) . x then ((f to_power a) to_power b) . x = 0 to_power b by A1, A4, POWER:def_2; then ((f to_power a) to_power b) . x = 0 by A1, POWER:def_2; hence ((f to_power a) to_power b) . x = (f to_power (a * b)) . x by A1, A7, A5, POWER:def_2; ::_thesis: verum end; hence ((f to_power a) to_power b) . x = (f to_power (a * b)) . x by A6, A1, MESFUNC6:51; ::_thesis: verum end; hence (f to_power a) to_power b = f to_power (a * b) by A2, FUNCT_1:2; ::_thesis: verum end; theorem Th7: :: LPSPACE2:7 for X being non empty set for a, b being Real for f being PartFunc of X,REAL st f is nonnegative & a > 0 & b > 0 holds (f to_power a) (#) (f to_power b) = f to_power (a + b) proof let X be non empty set ; ::_thesis: for a, b being Real for f being PartFunc of X,REAL st f is nonnegative & a > 0 & b > 0 holds (f to_power a) (#) (f to_power b) = f to_power (a + b) let a, b be Real; ::_thesis: for f being PartFunc of X,REAL st f is nonnegative & a > 0 & b > 0 holds (f to_power a) (#) (f to_power b) = f to_power (a + b) let f be PartFunc of X,REAL; ::_thesis: ( f is nonnegative & a > 0 & b > 0 implies (f to_power a) (#) (f to_power b) = f to_power (a + b) ) assume A1: ( f is nonnegative & a > 0 & b > 0 ) ; ::_thesis: (f to_power a) (#) (f to_power b) = f to_power (a + b) A2: ( dom (f to_power a) = dom f & dom (f to_power b) = dom f ) by MESFUN6C:def_4; A3: dom ((f to_power a) (#) (f to_power b)) = (dom (f to_power a)) /\ (dom (f to_power b)) by VALUED_1:def_4; then A4: dom ((f to_power a) (#) (f to_power b)) = dom (f to_power (a + b)) by A2, MESFUN6C:def_4; for x being set st x in dom ((f to_power a) (#) (f to_power b)) holds ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x proof let x be set ; ::_thesis: ( x in dom ((f to_power a) (#) (f to_power b)) implies ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x ) assume A5: x in dom ((f to_power a) (#) (f to_power b)) ; ::_thesis: ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x then ( (f to_power a) . x = (f . x) to_power a & (f to_power b) . x = (f . x) to_power b ) by A2, A3, MESFUN6C:def_4; then A6: ((f to_power a) (#) (f to_power b)) . x = ((f . x) to_power a) * ((f . x) to_power b) by A5, VALUED_1:def_4; A7: (f to_power (a + b)) . x = (f . x) to_power (a + b) by A4, A5, MESFUN6C:def_4; then A8: ( f . x > 0 implies ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x ) by A6, POWER:27; now__::_thesis:_(_f_._x_=_0_implies_((f_to_power_a)_(#)_(f_to_power_b))_._x_=_(f_to_power_(a_+_b))_._x_) assume A9: f . x = 0 ; ::_thesis: ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x then ((f to_power a) (#) (f to_power b)) . x = 0 * (0 to_power b) by A1, A6, POWER:def_2; hence ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x by A7, A1, A9, POWER:def_2; ::_thesis: verum end; hence ((f to_power a) (#) (f to_power b)) . x = (f to_power (a + b)) . x by A1, A8, MESFUNC6:51; ::_thesis: verum end; hence (f to_power a) (#) (f to_power b) = f to_power (a + b) by A4, FUNCT_1:2; ::_thesis: verum end; theorem Th8: :: LPSPACE2:8 for X being non empty set for f being PartFunc of X,REAL holds f to_power 1 = f proof let X be non empty set ; ::_thesis: for f being PartFunc of X,REAL holds f to_power 1 = f let f be PartFunc of X,REAL; ::_thesis: f to_power 1 = f A1: dom (f to_power 1) = dom f by MESFUN6C:def_4; for x being set st x in dom (f to_power 1) holds (f to_power 1) . x = f . x proof let x be set ; ::_thesis: ( x in dom (f to_power 1) implies (f to_power 1) . x = f . x ) assume x in dom (f to_power 1) ; ::_thesis: (f to_power 1) . x = f . x then (f to_power 1) . x = (f . x) to_power 1 by MESFUN6C:def_4; hence (f to_power 1) . x = f . x by POWER:25; ::_thesis: verum end; hence f to_power 1 = f by A1, FUNCT_1:2; ::_thesis: verum end; theorem Th9: :: LPSPACE2:9 for seq1, seq2 being Real_Sequence for k being positive Real st ( for n being Element of NAT holds ( seq1 . n = (seq2 . n) to_power k & seq2 . n >= 0 ) ) holds ( seq1 is convergent iff seq2 is convergent ) proof let seq1, seq2 be Real_Sequence; ::_thesis: for k being positive Real st ( for n being Element of NAT holds ( seq1 . n = (seq2 . n) to_power k & seq2 . n >= 0 ) ) holds ( seq1 is convergent iff seq2 is convergent ) let k be positive Real; ::_thesis: ( ( for n being Element of NAT holds ( seq1 . n = (seq2 . n) to_power k & seq2 . n >= 0 ) ) implies ( seq1 is convergent iff seq2 is convergent ) ) assume A1: for n being Element of NAT holds ( seq1 . n = (seq2 . n) to_power k & seq2 . n >= 0 ) ; ::_thesis: ( seq1 is convergent iff seq2 is convergent ) A2: for n being Element of NAT holds seq1 . n >= 0 proof let n be Element of NAT ; ::_thesis: seq1 . n >= 0 (seq2 . n) to_power k >= 0 by A1, Th4; hence seq1 . n >= 0 by A1; ::_thesis: verum end; thus ( seq1 is convergent implies seq2 is convergent ) ::_thesis: ( seq2 is convergent implies seq1 is convergent ) proof assume A3: seq1 is convergent ; ::_thesis: seq2 is convergent for n being Element of NAT holds seq2 . n = (seq1 . n) to_power (1 / k) proof let n be Element of NAT ; ::_thesis: seq2 . n = (seq1 . n) to_power (1 / k) (seq1 . n) to_power (1 / k) = ((seq2 . n) to_power k) to_power (1 / k) by A1 .= (seq2 . n) to_power (k * (1 / k)) by A1, HOLDER_1:2 .= (seq2 . n) to_power 1 by XCMPLX_1:106 ; hence seq2 . n = (seq1 . n) to_power (1 / k) by POWER:25; ::_thesis: verum end; hence seq2 is convergent by A2, A3, HOLDER_1:10; ::_thesis: verum end; assume seq2 is convergent ; ::_thesis: seq1 is convergent hence seq1 is convergent by A1, HOLDER_1:10; ::_thesis: verum end; theorem Th10: :: LPSPACE2:10 for seq being Real_Sequence for n, m being Element of NAT st m <= n holds ( abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= ((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m) & abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= (Partial_Sums (abs seq)) . n ) proof let seq be Real_Sequence; ::_thesis: for n, m being Element of NAT st m <= n holds ( abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= ((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m) & abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= (Partial_Sums (abs seq)) . n ) let n, m be Element of NAT ; ::_thesis: ( m <= n implies ( abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= ((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m) & abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= (Partial_Sums (abs seq)) . n ) ) assume A1: m <= n ; ::_thesis: ( abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= ((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m) & abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= (Partial_Sums (abs seq)) . n ) A2: for n being Element of NAT holds (abs seq) . n >= 0 proof let n be Element of NAT ; ::_thesis: (abs seq) . n >= 0 abs (seq . n) = (abs seq) . n by SEQ_1:12; hence (abs seq) . n >= 0 by COMPLEX1:46; ::_thesis: verum end; then A3: abs (((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m)) = ((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m) by A1, COMSEQ_3:9; (Partial_Sums (abs seq)) . m >= 0 by A2, SERIES_3:34; then abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= (((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m)) + ((Partial_Sums (abs seq)) . m) by A3, A1, SERIES_1:34, XREAL_1:38; hence ( abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= ((Partial_Sums (abs seq)) . n) - ((Partial_Sums (abs seq)) . m) & abs (((Partial_Sums seq) . n) - ((Partial_Sums seq) . m)) <= (Partial_Sums (abs seq)) . n ) by A3, A1, SERIES_1:34; ::_thesis: verum end; theorem Th11: :: LPSPACE2:11 for seq, seq2 being Real_Sequence for k being positive Real st seq is convergent & ( for n being Element of NAT holds seq2 . n = |.((lim seq) - (seq . n)).| to_power k ) holds ( seq2 is convergent & lim seq2 = 0 ) proof let seq, seq2 be Real_Sequence; ::_thesis: for k being positive Real st seq is convergent & ( for n being Element of NAT holds seq2 . n = |.((lim seq) - (seq . n)).| to_power k ) holds ( seq2 is convergent & lim seq2 = 0 ) let k be positive Real; ::_thesis: ( seq is convergent & ( for n being Element of NAT holds seq2 . n = |.((lim seq) - (seq . n)).| to_power k ) implies ( seq2 is convergent & lim seq2 = 0 ) ) set r = lim seq; assume A1: ( seq is convergent & ( for n being Element of NAT holds seq2 . n = |.((lim seq) - (seq . n)).| to_power k ) ) ; ::_thesis: ( seq2 is convergent & lim seq2 = 0 ) deffunc H1( Element of NAT ) -> Element of REAL = |.((lim seq) - (seq . $1)).|; consider seq1 being Real_Sequence such that A2: for n being Element of NAT holds seq1 . n = H1(n) from SEQ_1:sch_1(); deffunc H2( Element of NAT ) -> Element of REAL = lim seq; consider seq0 being Real_Sequence such that A3: for n being Element of NAT holds seq0 . n = H2(n) from SEQ_1:sch_1(); for n being Nat holds seq0 . n = lim seq proof let n be Nat; ::_thesis: seq0 . n = lim seq n in NAT by ORDINAL1:def_12; hence seq0 . n = lim seq by A3; ::_thesis: verum end; then A4: seq0 is constant by VALUED_0:def_18; then A5: seq0 - seq is convergent by A1; A6: ( dom seq0 = NAT & dom seq = NAT & dom (seq0 - seq) = NAT & dom seq1 = NAT ) by FUNCT_2:def_1; A7: dom (abs (seq0 - seq)) = dom (seq0 - seq) by VALUED_1:def_11; for n being Element of NAT holds (abs (seq0 - seq)) . n = seq1 . n proof let n be Element of NAT ; ::_thesis: (abs (seq0 - seq)) . n = seq1 . n seq1 . n = |.((lim seq) - (seq . n)).| by A2; then seq1 . n = |.((seq0 . n) - (seq . n)).| by A3; then seq1 . n = abs ((seq0 - seq) . n) by A6, VALUED_1:13; hence (abs (seq0 - seq)) . n = seq1 . n by A6, A7, VALUED_1:def_11; ::_thesis: verum end; then A8: abs (seq0 - seq) = seq1 by FUNCT_2:63; then A9: seq1 is convergent by A5; lim (seq0 - seq) = (seq0 . 0) - (lim seq) by A4, A1, SEQ_4:42; then lim (seq0 - seq) = (lim seq) - (lim seq) by A3; then A10: lim seq1 = 0 by A5, A8, COMPLEX1:44, SEQ_4:14; for n being Element of NAT holds ( seq2 . n = (seq1 . n) to_power k & seq1 . n >= 0 ) proof let n be Element of NAT ; ::_thesis: ( seq2 . n = (seq1 . n) to_power k & seq1 . n >= 0 ) |.((lim seq) - (seq . n)).| = seq1 . n by A2; hence ( seq2 . n = (seq1 . n) to_power k & seq1 . n >= 0 ) by A1, COMPLEX1:46; ::_thesis: verum end; then ( seq2 is convergent & lim seq2 = (lim seq1) to_power k ) by A9, HOLDER_1:10; hence ( seq2 is convergent & lim seq2 = 0 ) by A10, POWER:def_2; ::_thesis: verum end; Lm1: for seq being Real_Sequence for n being Element of NAT holds abs ((Partial_Sums seq) . n) <= (Partial_Sums (abs seq)) . n by NAGATA_2:13; begin theorem Th12: :: LPSPACE2:12 for k being positive Real for X being non empty set holds (X --> 0) to_power k = X --> 0 proof let k be positive Real; ::_thesis: for X being non empty set holds (X --> 0) to_power k = X --> 0 let X be non empty set ; ::_thesis: (X --> 0) to_power k = X --> 0 A1: dom ((X --> 0) to_power k) = dom (X --> 0) by MESFUN6C:def_4; now__::_thesis:_for_x_being_Element_of_X_st_x_in_dom_((X_-->_0)_to_power_k)_holds_ ((X_-->_0)_to_power_k)_._x_=_(X_-->_0)_._x let x be Element of X; ::_thesis: ( x in dom ((X --> 0) to_power k) implies ((X --> 0) to_power k) . x = (X --> 0) . x ) assume x in dom ((X --> 0) to_power k) ; ::_thesis: ((X --> 0) to_power k) . x = (X --> 0) . x then ((X --> 0) to_power k) . x = ((X --> 0) . x) to_power k by MESFUN6C:def_4; then ((X --> 0) to_power k) . x = 0 to_power k by FUNCOP_1:7; then ((X --> 0) to_power k) . x = 0 by POWER:def_2; hence ((X --> 0) to_power k) . x = (X --> 0) . x by FUNCOP_1:7; ::_thesis: verum end; hence (X --> 0) to_power k = X --> 0 by A1, PARTFUN1:5; ::_thesis: verum end; theorem Th13: :: LPSPACE2:13 for X being non empty set for f being PartFunc of X,REAL for D being set holds abs (f | D) = (abs f) | D proof let X be non empty set ; ::_thesis: for f being PartFunc of X,REAL for D being set holds abs (f | D) = (abs f) | D let f be PartFunc of X,REAL; ::_thesis: for D being set holds abs (f | D) = (abs f) | D let D be set ; ::_thesis: abs (f | D) = (abs f) | D A1: dom (abs (f | D)) = dom (f | D) by VALUED_1:def_11; then dom (abs (f | D)) = (dom f) /\ D by RELAT_1:61; then dom (abs (f | D)) = (dom (abs f)) /\ D by VALUED_1:def_11; then A2: dom (abs (f | D)) = dom ((abs f) | D) by RELAT_1:61; for x being Element of X st x in dom (abs (f | D)) holds (abs (f | D)) . x = ((abs f) | D) . x proof let x be Element of X; ::_thesis: ( x in dom (abs (f | D)) implies (abs (f | D)) . x = ((abs f) | D) . x ) assume A3: x in dom (abs (f | D)) ; ::_thesis: (abs (f | D)) . x = ((abs f) | D) . x then x in dom f by A1, RELAT_1:57; then A4: x in dom (abs f) by VALUED_1:def_11; (abs (f | D)) . x = abs ((f | D) . x) by A3, VALUED_1:def_11; then (abs (f | D)) . x = abs (f . x) by A3, A1, FUNCT_1:47; then (abs (f | D)) . x = (abs f) . x by A4, VALUED_1:def_11; hence (abs (f | D)) . x = ((abs f) | D) . x by A3, A2, FUNCT_1:47; ::_thesis: verum end; hence abs (f | D) = (abs f) | D by A2, PARTFUN1:5; ::_thesis: verum end; registration let X be non empty set ; let f be PartFunc of X,REAL; cluster|.f.| -> nonnegative ; coherence abs f is nonnegative proof now__::_thesis:_for_x_being_set_st_x_in_dom_(abs_f)_holds_ 0_<=_(abs_f)_._x let x be set ; ::_thesis: ( x in dom (abs f) implies 0 <= (abs f) . x ) assume x in dom (abs f) ; ::_thesis: 0 <= (abs f) . x then (abs f) . x = abs (f . x) by VALUED_1:def_11; hence 0 <= (abs f) . x by COMPLEX1:46; ::_thesis: verum end; hence abs f is nonnegative by MESFUNC6:52; ::_thesis: verum end; end; theorem Th14: :: LPSPACE2:14 for X being non empty set for f being PartFunc of X,REAL st f is nonnegative holds abs f = f proof let X be non empty set ; ::_thesis: for f being PartFunc of X,REAL st f is nonnegative holds abs f = f let f be PartFunc of X,REAL; ::_thesis: ( f is nonnegative implies abs f = f ) A1: dom f = dom (abs f) by VALUED_1:def_11; assume A2: f is nonnegative ; ::_thesis: abs f = f now__::_thesis:_for_x_being_Element_of_X_st_x_in_dom_f_holds_ (abs_f)_._x_=_f_._x let x be Element of X; ::_thesis: ( x in dom f implies (abs f) . x = f . x ) A3: f . x >= 0 by A2, MESFUNC6:51; assume x in dom f ; ::_thesis: (abs f) . x = f . x then x in dom (abs f) by VALUED_1:def_11; then (abs f) . x = abs (f . x) by VALUED_1:def_11; hence (abs f) . x = f . x by A3, ABSVALUE:def_1; ::_thesis: verum end; hence abs f = f by A1, PARTFUN1:5; ::_thesis: verum end; theorem Th15: :: LPSPACE2:15 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st X = dom f & ( for x being Element of X st x in dom f holds 0 = f . x ) holds ( f is_integrable_on M & Integral (M,f) = 0 ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st X = dom f & ( for x being Element of X st x in dom f holds 0 = f . x ) holds ( f is_integrable_on M & Integral (M,f) = 0 ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL st X = dom f & ( for x being Element of X st x in dom f holds 0 = f . x ) holds ( f is_integrable_on M & Integral (M,f) = 0 ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL st X = dom f & ( for x being Element of X st x in dom f holds 0 = f . x ) holds ( f is_integrable_on M & Integral (M,f) = 0 ) let f be PartFunc of X,REAL; ::_thesis: ( X = dom f & ( for x being Element of X st x in dom f holds 0 = f . x ) implies ( f is_integrable_on M & Integral (M,f) = 0 ) ) assume A1: ( X = dom f & ( for x being Element of X st x in dom f holds 0 = f . x ) ) ; ::_thesis: ( f is_integrable_on M & Integral (M,f) = 0 ) X is Element of S by MEASURE1:7; then ( R_EAL f is_integrable_on M & Integral (M,(R_EAL f)) = 0 ) by A1, LPSPACE1:22; hence ( f is_integrable_on M & Integral (M,f) = 0 ) by MESFUNC6:def_4; ::_thesis: verum end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func Lp_Functions (M,k) -> non empty Subset of (RLSp_PFunct X) equals :: LPSPACE2:def 2 { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } ; correctness coherence { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } is non empty Subset of (RLSp_PFunct X); proof set V = { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } ; A1: { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } c= PFuncs (X,REAL) proof let x be set ; :: according to TARSKI:def_3 ::_thesis: ( not x in { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } or x in PFuncs (X,REAL) ) assume x in { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } ; ::_thesis: x in PFuncs (X,REAL) then ex f being PartFunc of X,REAL st ( x = f & ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) ) ; hence x in PFuncs (X,REAL) by PARTFUN1:45; ::_thesis: verum end; reconsider g = X --> 0 as Function of X,REAL by FUNCOP_1:46; reconsider Ef = X as Element of S by MEASURE1:34; set h = (abs g) to_power k; A2: dom g = X by FUNCOP_1:13; for x being set st x in dom g holds g . x = 0 by FUNCOP_1:7; then A3: g is_measurable_on Ef by A2, LPSPACE1:52; Ef ` = {} by XBOOLE_1:37; then A4: M . (Ef `) = 0 by VALUED_0:def_19; for x being set st x in dom (X --> 0) holds 0 <= (X --> 0) . x ; then abs g = X --> 0 by Th14, MESFUNC6:52; then A5: (abs g) to_power k = g by Th12; then for x being Element of X st x in dom ((abs g) to_power k) holds ((abs g) to_power k) . x = 0 by FUNCOP_1:7; then (abs g) to_power k is_integrable_on M by Th15, A5, A2; then g in { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } by A3, A4, A2; hence { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } is non empty Subset of (RLSp_PFunct X) by A1; ::_thesis: verum end; end; :: deftheorem defines Lp_Functions LPSPACE2:def_2_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds Lp_Functions (M,k) = { f where f is PartFunc of X,REAL : ex Ef being Element of S st ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) } ; theorem Th16: :: LPSPACE2:16 for a, b, k being Real st k > 0 holds ( (abs (a + b)) to_power k <= ((abs a) + (abs b)) to_power k & ((abs a) + (abs b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k & (abs (a + b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k ) proof let a, b, k be Real; ::_thesis: ( k > 0 implies ( (abs (a + b)) to_power k <= ((abs a) + (abs b)) to_power k & ((abs a) + (abs b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k & (abs (a + b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k ) ) assume A1: k > 0 ; ::_thesis: ( (abs (a + b)) to_power k <= ((abs a) + (abs b)) to_power k & ((abs a) + (abs b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k & (abs (a + b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k ) A2: abs (a + b) <= (abs a) + (abs b) by ABSVALUE:9; ( abs a <= max ((abs a),(abs b)) & abs b <= max ((abs a),(abs b)) ) by XXREAL_0:25; then A3: (abs a) + (abs b) <= (max ((abs a),(abs b))) + (max ((abs a),(abs b))) by XREAL_1:7; then A4: abs (a + b) <= 2 * (max ((abs a),(abs b))) by A2, XXREAL_0:2; 0 <= abs (a + b) by COMPLEX1:46; hence ( (abs (a + b)) to_power k <= ((abs a) + (abs b)) to_power k & ((abs a) + (abs b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k & (abs (a + b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k ) by A1, A2, A3, A4, HOLDER_1:3; ::_thesis: verum end; theorem Th17: :: LPSPACE2:17 for a, b, k being Real st a >= 0 & b >= 0 & k > 0 holds (max (a,b)) to_power k <= (a to_power k) + (b to_power k) proof let a, b, k be Real; ::_thesis: ( a >= 0 & b >= 0 & k > 0 implies (max (a,b)) to_power k <= (a to_power k) + (b to_power k) ) assume A1: ( a >= 0 & b >= 0 & k > 0 ) ; ::_thesis: (max (a,b)) to_power k <= (a to_power k) + (b to_power k) percases ( ( a <> 0 & b <> 0 ) or a = 0 or b = 0 ) ; suppose ( a <> 0 & b <> 0 ) ; ::_thesis: (max (a,b)) to_power k <= (a to_power k) + (b to_power k) then A2: ( a to_power k >= 0 & b to_power k >= 0 ) by A1, POWER:34; ( max (a,b) = a or max (a,b) = b ) by XXREAL_0:def_10; hence (max (a,b)) to_power k <= (a to_power k) + (b to_power k) by A2, XREAL_1:40; ::_thesis: verum end; supposeA3: a = 0 ; ::_thesis: (max (a,b)) to_power k <= (a to_power k) + (b to_power k) then a to_power k = 0 by A1, POWER:def_2; hence (max (a,b)) to_power k <= (a to_power k) + (b to_power k) by A1, A3, XXREAL_0:def_10; ::_thesis: verum end; supposeA4: b = 0 ; ::_thesis: (max (a,b)) to_power k <= (a to_power k) + (b to_power k) then b to_power k = 0 by A1, POWER:def_2; hence (max (a,b)) to_power k <= (a to_power k) + (b to_power k) by A1, A4, XXREAL_0:def_10; ::_thesis: verum end; end; end; theorem Th18: :: LPSPACE2:18 for X being non empty set for f being PartFunc of X,REAL for a, b being Real st b > 0 holds ((abs a) to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b proof let X be non empty set ; ::_thesis: for f being PartFunc of X,REAL for a, b being Real st b > 0 holds ((abs a) to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b let f be PartFunc of X,REAL; ::_thesis: for a, b being Real st b > 0 holds ((abs a) to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b let a, b be Real; ::_thesis: ( b > 0 implies ((abs a) to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b ) assume A1: b > 0 ; ::_thesis: ((abs a) to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b A2: ( dom (((abs a) to_power b) (#) ((abs f) to_power b)) = dom ((abs f) to_power b) & dom (a (#) f) = dom f ) by VALUED_1:def_5; A3: ( dom ((abs f) to_power b) = dom (abs f) & dom (abs (a (#) f)) = dom ((abs (a (#) f)) to_power b) ) by MESFUN6C:def_4; A4: ( dom (abs f) = dom f & dom (abs (a (#) f)) = dom (a (#) f) ) by VALUED_1:def_11; for x being Element of X st x in dom (((abs a) to_power b) (#) ((abs f) to_power b)) holds (((abs a) to_power b) (#) ((abs f) to_power b)) . x = ((abs (a (#) f)) to_power b) . x proof let x be Element of X; ::_thesis: ( x in dom (((abs a) to_power b) (#) ((abs f) to_power b)) implies (((abs a) to_power b) (#) ((abs f) to_power b)) . x = ((abs (a (#) f)) to_power b) . x ) assume A5: x in dom (((abs a) to_power b) (#) ((abs f) to_power b)) ; ::_thesis: (((abs a) to_power b) (#) ((abs f) to_power b)) . x = ((abs (a (#) f)) to_power b) . x A6: ( abs (f . x) >= 0 & abs a >= 0 ) by COMPLEX1:46; (((abs a) to_power b) (#) ((abs f) to_power b)) . x = ((abs a) to_power b) * (((abs f) to_power b) . x) by A5, VALUED_1:def_5 .= ((abs a) to_power b) * (((abs f) . x) to_power b) by A2, A5, MESFUN6C:def_4 .= ((abs a) to_power b) * ((abs (f . x)) to_power b) by VALUED_1:18 .= ((abs a) * (abs (f . x))) to_power b by A1, A6, Th5 .= (abs (a * (f . x))) to_power b by COMPLEX1:65 .= (abs ((a (#) f) . x)) to_power b by VALUED_1:6 .= ((abs (a (#) f)) . x) to_power b by VALUED_1:18 ; hence (((abs a) to_power b) (#) ((abs f) to_power b)) . x = ((abs (a (#) f)) to_power b) . x by A2, A3, A4, A5, MESFUN6C:def_4; ::_thesis: verum end; hence ((abs a) to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b by A2, A3, A4, PARTFUN1:5; ::_thesis: verum end; theorem Th19: :: LPSPACE2:19 for X being non empty set for f being PartFunc of X,REAL for a, b being Real st a > 0 & b > 0 holds (a to_power b) (#) ((abs f) to_power b) = (a (#) (abs f)) to_power b proof let X be non empty set ; ::_thesis: for f being PartFunc of X,REAL for a, b being Real st a > 0 & b > 0 holds (a to_power b) (#) ((abs f) to_power b) = (a (#) (abs f)) to_power b let f be PartFunc of X,REAL; ::_thesis: for a, b being Real st a > 0 & b > 0 holds (a to_power b) (#) ((abs f) to_power b) = (a (#) (abs f)) to_power b let a, b be Real; ::_thesis: ( a > 0 & b > 0 implies (a to_power b) (#) ((abs f) to_power b) = (a (#) (abs f)) to_power b ) assume A1: ( a > 0 & b > 0 ) ; ::_thesis: (a to_power b) (#) ((abs f) to_power b) = (a (#) (abs f)) to_power b then A2: abs a = a by COMPLEX1:43; then (a to_power b) (#) ((abs f) to_power b) = (abs (a (#) f)) to_power b by A1, Th18; hence (a to_power b) (#) ((abs f) to_power b) = (a (#) (abs f)) to_power b by A2, RFUNCT_1:25; ::_thesis: verum end; theorem Th20: :: LPSPACE2:20 for X being non empty set for f being PartFunc of X,REAL for k being real number for E being set holds (f | E) to_power k = (f to_power k) | E proof let X be non empty set ; ::_thesis: for f being PartFunc of X,REAL for k being real number for E being set holds (f | E) to_power k = (f to_power k) | E let f be PartFunc of X,REAL; ::_thesis: for k being real number for E being set holds (f | E) to_power k = (f to_power k) | E let k be real number ; ::_thesis: for E being set holds (f | E) to_power k = (f to_power k) | E let E be set ; ::_thesis: (f | E) to_power k = (f to_power k) | E A1: dom ((f | E) to_power k) = dom (f | E) by MESFUN6C:def_4; then dom ((f | E) to_power k) = (dom f) /\ E by RELAT_1:61; then A2: dom ((f | E) to_power k) = (dom (f to_power k)) /\ E by MESFUN6C:def_4; then A3: dom ((f | E) to_power k) = dom ((f to_power k) | E) by RELAT_1:61; now__::_thesis:_for_x_being_Element_of_X_st_x_in_dom_((f_|_E)_to_power_k)_holds_ ((f_|_E)_to_power_k)_._x_=_((f_to_power_k)_|_E)_._x let x be Element of X; ::_thesis: ( x in dom ((f | E) to_power k) implies ((f | E) to_power k) . x = ((f to_power k) | E) . x ) assume A4: x in dom ((f | E) to_power k) ; ::_thesis: ((f | E) to_power k) . x = ((f to_power k) | E) . x then ((f | E) to_power k) . x = ((f | E) . x) to_power k by MESFUN6C:def_4; then A5: ((f | E) to_power k) . x = (f . x) to_power k by A1, A4, FUNCT_1:47; x in dom (f to_power k) by A2, A4, XBOOLE_0:def_4; then ((f | E) to_power k) . x = (f to_power k) . x by A5, MESFUN6C:def_4; hence ((f | E) to_power k) . x = ((f to_power k) | E) . x by A4, A3, FUNCT_1:47; ::_thesis: verum end; hence (f | E) to_power k = (f to_power k) | E by A3, PARTFUN1:5; ::_thesis: verum end; theorem Th21: :: LPSPACE2:21 for a, b, k being Real st k > 0 holds (abs (a + b)) to_power k <= (2 to_power k) * (((abs a) to_power k) + ((abs b) to_power k)) proof let a, b, k be Real; ::_thesis: ( k > 0 implies (abs (a + b)) to_power k <= (2 to_power k) * (((abs a) to_power k) + ((abs b) to_power k)) ) assume A1: k > 0 ; ::_thesis: (abs (a + b)) to_power k <= (2 to_power k) * (((abs a) to_power k) + ((abs b) to_power k)) then A2: (abs (a + b)) to_power k <= (2 * (max ((abs a),(abs b)))) to_power k by Th16; A3: ( abs a >= 0 & abs b >= 0 ) by COMPLEX1:46; then A4: (max ((abs a),(abs b))) to_power k <= ((abs a) to_power k) + ((abs b) to_power k) by A1, Th17; ( max ((abs a),(abs b)) = abs a or max ((abs a),(abs b)) = abs b ) by XXREAL_0:16; then A5: (2 * (max ((abs a),(abs b)))) to_power k = (2 to_power k) * ((max ((abs a),(abs b))) to_power k) by A1, A3, Th5; 2 to_power k > 0 by POWER:34; then (2 to_power k) * ((max ((abs a),(abs b))) to_power k) <= (2 to_power k) * (((abs a) to_power k) + ((abs b) to_power k)) by A4, XREAL_1:64; hence (abs (a + b)) to_power k <= (2 to_power k) * (((abs a) to_power k) + ((abs b) to_power k)) by A2, A5, XXREAL_0:2; ::_thesis: verum end; theorem Th22: :: LPSPACE2:22 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for f, g being PartFunc of X,REAL st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for f, g being PartFunc of X,REAL st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real for f, g being PartFunc of X,REAL st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) let M be sigma_Measure of S; ::_thesis: for k being positive Real for f, g being PartFunc of X,REAL st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) let k be positive Real; ::_thesis: for f, g being PartFunc of X,REAL st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) let f, g be PartFunc of X,REAL; ::_thesis: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) implies ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) ) assume A1: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) ; ::_thesis: ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) then A2: ex f1 being PartFunc of X,REAL st ( f = f1 & ex Ev being Element of S st ( M . (Ev `) = 0 & dom f1 = Ev & f1 is_measurable_on Ev & (abs f1) to_power k is_integrable_on M ) ) ; ex g1 being PartFunc of X,REAL st ( g = g1 & ex Eu being Element of S st ( M . (Eu `) = 0 & dom g1 = Eu & g1 is_measurable_on Eu & (abs g1) to_power k is_integrable_on M ) ) by A1; hence ( (abs f) to_power k is_integrable_on M & (abs g) to_power k is_integrable_on M & ((abs f) to_power k) + ((abs g) to_power k) is_integrable_on M ) by A2, MESFUNC6:100; ::_thesis: verum end; theorem Th23: :: LPSPACE2:23 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( X --> 0 is PartFunc of X,REAL & X --> 0 in Lp_Functions (M,k) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( X --> 0 is PartFunc of X,REAL & X --> 0 in Lp_Functions (M,k) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real holds ( X --> 0 is PartFunc of X,REAL & X --> 0 in Lp_Functions (M,k) ) let M be sigma_Measure of S; ::_thesis: for k being positive Real holds ( X --> 0 is PartFunc of X,REAL & X --> 0 in Lp_Functions (M,k) ) let k be positive Real; ::_thesis: ( X --> 0 is PartFunc of X,REAL & X --> 0 in Lp_Functions (M,k) ) reconsider g = X --> 0 as Function of X,REAL by FUNCOP_1:46; reconsider ND = X as Element of S by MEASURE1:34; ND ` = {} by XBOOLE_1:37; then A1: M . (ND `) = 0 by VALUED_0:def_19; A2: dom g = X by FUNCT_2:def_1; for x being Element of X st x in dom g holds g . x = 0 by FUNCOP_1:7; then A3: g is_integrable_on M by A2, Th15; for x being set st x in dom g holds 0 <= g . x ; then abs g = g by Th14, MESFUNC6:52; then A4: (abs g) to_power k = g by Th12; for x being set st x in dom g holds g . x = 0 by FUNCOP_1:7; then g is_measurable_on ND by A2, LPSPACE1:52; hence ( X --> 0 is PartFunc of X,REAL & X --> 0 in Lp_Functions (M,k) ) by A1, A2, A3, A4; ::_thesis: verum end; theorem Th24: :: LPSPACE2:24 for X being non empty set for k being Real st k > 0 holds for f, g being PartFunc of X,REAL for x being Element of X st x in (dom f) /\ (dom g) holds ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x proof let X be non empty set ; ::_thesis: for k being Real st k > 0 holds for f, g being PartFunc of X,REAL for x being Element of X st x in (dom f) /\ (dom g) holds ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x let k be Element of REAL ; ::_thesis: ( k > 0 implies for f, g being PartFunc of X,REAL for x being Element of X st x in (dom f) /\ (dom g) holds ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x ) assume A1: k > 0 ; ::_thesis: for f, g being PartFunc of X,REAL for x being Element of X st x in (dom f) /\ (dom g) holds ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x let f, g be PartFunc of X,REAL; ::_thesis: for x being Element of X st x in (dom f) /\ (dom g) holds ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x let x be Element of X; ::_thesis: ( x in (dom f) /\ (dom g) implies ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x ) assume A2: x in (dom f) /\ (dom g) ; ::_thesis: ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x A3: dom (f + g) = (dom f) /\ (dom g) by VALUED_1:def_1; then dom (abs (f + g)) = (dom f) /\ (dom g) by VALUED_1:def_11; then x in dom ((abs (f + g)) to_power k) by A2, MESFUN6C:def_4; then A4: ((abs (f + g)) to_power k) . x = ((abs (f + g)) . x) to_power k by MESFUN6C:def_4 .= (abs ((f + g) . x)) to_power k by VALUED_1:18 .= (abs ((f . x) + (g . x))) to_power k by A3, A2, VALUED_1:def_1 ; ( dom (abs f) = dom f & dom (abs g) = dom g ) by VALUED_1:def_11; then ( x in dom (abs f) & x in dom (abs g) ) by A2, XBOOLE_0:def_4; then A5: ( x in dom ((abs f) to_power k) & x in dom ((abs g) to_power k) ) by MESFUN6C:def_4; ( (abs (f . x)) to_power k = ((abs f) . x) to_power k & (abs (g . x)) to_power k = ((abs g) . x) to_power k ) by VALUED_1:18; then A6: ( (abs (f . x)) to_power k = ((abs f) to_power k) . x & (abs (g . x)) to_power k = ((abs g) to_power k) . x ) by A5, MESFUN6C:def_4; dom (((abs f) to_power k) + ((abs g) to_power k)) = (dom ((abs f) to_power k)) /\ (dom ((abs g) to_power k)) by VALUED_1:def_1; then x in dom (((abs f) to_power k) + ((abs g) to_power k)) by A5, XBOOLE_0:def_4; then (2 to_power k) * (((abs (f . x)) to_power k) + ((abs (g . x)) to_power k)) = (2 to_power k) * ((((abs f) to_power k) + ((abs g) to_power k)) . x) by A6, VALUED_1:def_1 .= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x by VALUED_1:6 ; hence ((abs (f + g)) to_power k) . x <= ((2 to_power k) (#) (((abs f) to_power k) + ((abs g) to_power k))) . x by A1, A4, Th21; ::_thesis: verum end; theorem Th25: :: LPSPACE2:25 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f + g in Lp_Functions (M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f + g in Lp_Functions (M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f + g in Lp_Functions (M,k) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f + g in Lp_Functions (M,k) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f + g in Lp_Functions (M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) implies f + g in Lp_Functions (M,k) ) set W = Lp_Functions (M,k); assume A1: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) ; ::_thesis: f + g in Lp_Functions (M,k) then consider f1 being PartFunc of X,REAL such that A2: ( f1 = f & ex Ef1 being Element of S st ( M . (Ef1 `) = 0 & dom f1 = Ef1 & f1 is_measurable_on Ef1 & (abs f1) to_power k is_integrable_on M ) ) ; consider Ef being Element of S such that A3: ( M . (Ef `) = 0 & dom f1 = Ef & f1 is_measurable_on Ef & (abs f1) to_power k is_integrable_on M ) by A2; consider g1 being PartFunc of X,REAL such that A4: ( g1 = g & ex Eg1 being Element of S st ( M . (Eg1 `) = 0 & dom g1 = Eg1 & g1 is_measurable_on Eg1 & (abs g1) to_power k is_integrable_on M ) ) by A1; consider Eg being Element of S such that A5: ( M . (Eg `) = 0 & dom g1 = Eg & g1 is_measurable_on Eg & (abs g1) to_power k is_integrable_on M ) by A4; A6: dom (f1 + g1) = Ef /\ Eg by A3, A5, VALUED_1:def_1; set Efg = Ef /\ Eg; set s = (abs (f1 + g1)) to_power k; set t = (2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k)); A7: (Ef /\ Eg) ` = (X \ Ef) \/ (X \ Eg) by XBOOLE_1:54; ( Ef ` is Element of S & Eg ` is Element of S ) by MEASURE1:34; then ( Ef ` is measure_zero of M & Eg ` is measure_zero of M ) by A3, A5, MEASURE1:def_7; then (Ef `) \/ (Eg `) is measure_zero of M by MEASURE1:37; then A8: M . ((Ef /\ Eg) `) = 0 by A7, MEASURE1:def_7; ( f1 is_measurable_on Ef /\ Eg & g1 is_measurable_on Ef /\ Eg ) by A3, A5, MESFUNC6:16, XBOOLE_1:17; then A9: f1 + g1 is_measurable_on Ef /\ Eg by MESFUNC6:26; then A10: abs (f1 + g1) is_measurable_on Ef /\ Eg by A6, MESFUNC6:48; ((abs f1) to_power k) + ((abs g1) to_power k) is_integrable_on M by A1, A2, A4, Th22; then A11: (2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k)) is_integrable_on M by MESFUNC6:102; A12: ( dom (abs f1) = dom f1 & dom (abs g1) = dom g1 & dom (abs (f1 + g1)) = dom (f1 + g1) ) by VALUED_1:def_11; then A13: (abs (f1 + g1)) to_power k is_measurable_on Ef /\ Eg by A6, A10, MESFUN6C:29; A14: abs ((abs (f1 + g1)) to_power k) = (abs (f1 + g1)) to_power k by Th14; A15: dom ((abs (f1 + g1)) to_power k) = Ef /\ Eg by A6, A12, MESFUN6C:def_4; A16: dom ((2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k))) = dom (((abs f1) to_power k) + ((abs g1) to_power k)) by VALUED_1:def_5 .= (dom ((abs f1) to_power k)) /\ (dom ((abs g1) to_power k)) by VALUED_1:def_1 .= (dom (abs f1)) /\ (dom ((abs g1) to_power k)) by MESFUN6C:def_4 .= (dom (abs f1)) /\ (dom (abs g1)) by MESFUN6C:def_4 .= dom (f1 + g1) by A12, VALUED_1:def_1 .= dom ((abs (f1 + g1)) to_power k) by A12, MESFUN6C:def_4 ; now__::_thesis:_for_x_being_Element_of_X_st_x_in_dom_((abs_(f1_+_g1))_to_power_k)_holds_ abs_(((abs_(f1_+_g1))_to_power_k)_._x)_<=_((2_to_power_k)_(#)_(((abs_f1)_to_power_k)_+_((abs_g1)_to_power_k)))_._x let x be Element of X; ::_thesis: ( x in dom ((abs (f1 + g1)) to_power k) implies abs (((abs (f1 + g1)) to_power k) . x) <= ((2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k))) . x ) assume x in dom ((abs (f1 + g1)) to_power k) ; ::_thesis: abs (((abs (f1 + g1)) to_power k) . x) <= ((2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k))) . x then (abs ((abs (f1 + g1)) to_power k)) . x <= ((2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k))) . x by A14, Th24, A3, A5, A15; hence abs (((abs (f1 + g1)) to_power k) . x) <= ((2 to_power k) (#) (((abs f1) to_power k) + ((abs g1) to_power k))) . x by VALUED_1:18; ::_thesis: verum end; then (abs (f1 + g1)) to_power k is_integrable_on M by A13, A15, A16, A11, MESFUNC6:96; hence f + g in Lp_Functions (M,k) by A2, A4, A8, A6, A9; ::_thesis: verum end; theorem Th26: :: LPSPACE2:26 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) holds a (#) f in Lp_Functions (M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) holds a (#) f in Lp_Functions (M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) holds a (#) f in Lp_Functions (M,k) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) holds a (#) f in Lp_Functions (M,k) let f be PartFunc of X,REAL; ::_thesis: for a being Real for k being positive Real st f in Lp_Functions (M,k) holds a (#) f in Lp_Functions (M,k) let a be Real; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) holds a (#) f in Lp_Functions (M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) implies a (#) f in Lp_Functions (M,k) ) assume f in Lp_Functions (M,k) ; ::_thesis: a (#) f in Lp_Functions (M,k) then consider f1 being PartFunc of X,REAL such that A1: ( f1 = f & ex Ef1 being Element of S st ( M . (Ef1 `) = 0 & dom f1 = Ef1 & f1 is_measurable_on Ef1 & (abs f1) to_power k is_integrable_on M ) ) ; consider Ef being Element of S such that A2: ( M . (Ef `) = 0 & dom f1 = Ef & f1 is_measurable_on Ef & (abs f1) to_power k is_integrable_on M ) by A1; A3: ( dom (a (#) f1) = Ef & a (#) f1 is_measurable_on Ef ) by A2, MESFUNC6:21, VALUED_1:def_5; ((abs a) to_power k) (#) ((abs f1) to_power k) is_integrable_on M by A1, MESFUNC6:102; then (abs (a (#) f1)) to_power k is_integrable_on M by Th18; hence a (#) f in Lp_Functions (M,k) by A1, A2, A3; ::_thesis: verum end; theorem Th27: :: LPSPACE2:27 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f - g in Lp_Functions (M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f - g in Lp_Functions (M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f - g in Lp_Functions (M,k) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f - g in Lp_Functions (M,k) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) holds f - g in Lp_Functions (M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) implies f - g in Lp_Functions (M,k) ) assume A1: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) ; ::_thesis: f - g in Lp_Functions (M,k) then (- 1) (#) g in Lp_Functions (M,k) by Th26; hence f - g in Lp_Functions (M,k) by Th25, A1; ::_thesis: verum end; theorem Th28: :: LPSPACE2:28 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds abs f in Lp_Functions (M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds abs f in Lp_Functions (M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds abs f in Lp_Functions (M,k) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds abs f in Lp_Functions (M,k) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) holds abs f in Lp_Functions (M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) implies abs f in Lp_Functions (M,k) ) set W = Lp_Functions (M,k); assume f in Lp_Functions (M,k) ; ::_thesis: abs f in Lp_Functions (M,k) then consider f1 being PartFunc of X,REAL such that A1: ( f1 = f & ex Ef1 being Element of S st ( M . (Ef1 `) = 0 & dom f1 = Ef1 & f1 is_measurable_on Ef1 & (abs f1) to_power k is_integrable_on M ) ) ; consider Ef being Element of S such that A2: ( M . (Ef `) = 0 & dom f1 = Ef & f1 is_measurable_on Ef & (abs f1) to_power k is_integrable_on M ) by A1; dom (abs f1) = Ef by A2, VALUED_1:def_11; then ex Ef being Element of S st ( M . (Ef `) = 0 & dom (abs f1) = Ef & abs f1 is_measurable_on Ef & (abs (abs f1)) to_power k is_integrable_on M ) by A2, MESFUNC6:48; hence abs f in Lp_Functions (M,k) by A1; ::_thesis: verum end; Lm2: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( Lp_Functions (M,k) is add-closed & Lp_Functions (M,k) is multi-closed ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( Lp_Functions (M,k) is add-closed & Lp_Functions (M,k) is multi-closed ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real holds ( Lp_Functions (M,k) is add-closed & Lp_Functions (M,k) is multi-closed ) let M be sigma_Measure of S; ::_thesis: for k being positive Real holds ( Lp_Functions (M,k) is add-closed & Lp_Functions (M,k) is multi-closed ) let k be positive Real; ::_thesis: ( Lp_Functions (M,k) is add-closed & Lp_Functions (M,k) is multi-closed ) set W = Lp_Functions (M,k); now__::_thesis:_for_v,_u_being_Element_of_the_carrier_of_(RLSp_PFunct_X)_st_v_in_Lp_Functions_(M,k)_&_u_in_Lp_Functions_(M,k)_holds_ v_+_u_in_Lp_Functions_(M,k) let v, u be Element of the carrier of (RLSp_PFunct X); ::_thesis: ( v in Lp_Functions (M,k) & u in Lp_Functions (M,k) implies v + u in Lp_Functions (M,k) ) assume A1: ( v in Lp_Functions (M,k) & u in Lp_Functions (M,k) ) ; ::_thesis: v + u in Lp_Functions (M,k) then consider v1 being PartFunc of X,REAL such that A2: ( v1 = v & ex ND being Element of S st ( M . (ND `) = 0 & dom v1 = ND & v1 is_measurable_on ND & (abs v1) to_power k is_integrable_on M ) ) ; consider u1 being PartFunc of X,REAL such that A3: ( u1 = u & ex ND being Element of S st ( M . (ND `) = 0 & dom u1 = ND & u1 is_measurable_on ND & (abs u1) to_power k is_integrable_on M ) ) by A1; reconsider h = v + u as Element of PFuncs (X,REAL) ; ( dom h = (dom v1) /\ (dom u1) & ( for x being set st x in dom h holds h . x = (v1 . x) + (u1 . x) ) ) by A2, A3, LPSPACE1:6; then v + u = v1 + u1 by VALUED_1:def_1; hence v + u in Lp_Functions (M,k) by A1, A2, A3, Th25; ::_thesis: verum end; hence Lp_Functions (M,k) is add-closed by IDEAL_1:def_1; ::_thesis: Lp_Functions (M,k) is multi-closed now__::_thesis:_for_a_being_Real for_u_being_VECTOR_of_(RLSp_PFunct_X)_st_u_in_Lp_Functions_(M,k)_holds_ a_*_u_in_Lp_Functions_(M,k) let a be Real; ::_thesis: for u being VECTOR of (RLSp_PFunct X) st u in Lp_Functions (M,k) holds a * u in Lp_Functions (M,k) let u be VECTOR of (RLSp_PFunct X); ::_thesis: ( u in Lp_Functions (M,k) implies a * u in Lp_Functions (M,k) ) assume A4: u in Lp_Functions (M,k) ; ::_thesis: a * u in Lp_Functions (M,k) then consider u1 being PartFunc of X,REAL such that A5: ( u1 = u & ex ND being Element of S st ( M . (ND `) = 0 & dom u1 = ND & u1 is_measurable_on ND & (abs u1) to_power k is_integrable_on M ) ) ; reconsider h = a * u as Element of PFuncs (X,REAL) ; A6: ( dom h = dom u1 & ( for x being Element of X st x in dom u1 holds h . x = a * (u1 . x) ) ) by A5, LPSPACE1:9; then for x being set st x in dom h holds h . x = a * (u1 . x) ; then a * u = a (#) u1 by A6, VALUED_1:def_5; hence a * u in Lp_Functions (M,k) by Th26, A4, A5; ::_thesis: verum end; hence Lp_Functions (M,k) is multi-closed by LPSPACE1:def_1; ::_thesis: verum end; registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; cluster Lp_Functions (M,k) -> non empty add-closed multi-closed ; coherence ( Lp_Functions (M,k) is multi-closed & Lp_Functions (M,k) is add-closed ) by Lm2; end; Lm3: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real holds ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) let M be sigma_Measure of S; ::_thesis: for k being positive Real holds ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) let k be positive Real; ::_thesis: ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) 0. (RLSp_PFunct X) in Lp_Functions (M,k) by Th23; hence ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) by LPSPACE1:3; ::_thesis: verum end; registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; cluster RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) -> Abelian add-associative right_zeroed vector-distributive scalar-distributive scalar-associative scalar-unital ; coherence ( RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is Abelian & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is add-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is right_zeroed & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is vector-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-distributive & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-associative & RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is scalar-unital ) by Lm3; end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func RLSp_LpFunct (M,k) -> non empty strict Abelian add-associative right_zeroed vector-distributive scalar-distributive scalar-associative scalar-unital RLSStruct equals :: LPSPACE2:def 3 RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #); coherence RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #) is non empty strict Abelian add-associative right_zeroed vector-distributive scalar-distributive scalar-associative scalar-unital RLSStruct ; end; :: deftheorem defines RLSp_LpFunct LPSPACE2:def_3_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds RLSp_LpFunct (M,k) = RLSStruct(# (Lp_Functions (M,k)),(In ((0. (RLSp_PFunct X)),(Lp_Functions (M,k)))),(add| ((Lp_Functions (M,k)),(RLSp_PFunct X))),(Mult_ (Lp_Functions (M,k))) #); begin theorem Th29: :: LPSPACE2:29 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_LpFunct (M,k)) st f = v & g = u holds f + g = v + u proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_LpFunct (M,k)) st f = v & g = u holds f + g = v + u let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_LpFunct (M,k)) st f = v & g = u holds f + g = v + u let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_LpFunct (M,k)) st f = v & g = u holds f + g = v + u let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real for v, u being VECTOR of (RLSp_LpFunct (M,k)) st f = v & g = u holds f + g = v + u let k be positive Real; ::_thesis: for v, u being VECTOR of (RLSp_LpFunct (M,k)) st f = v & g = u holds f + g = v + u let v, u be VECTOR of (RLSp_LpFunct (M,k)); ::_thesis: ( f = v & g = u implies f + g = v + u ) reconsider v2 = v, u2 = u as VECTOR of (RLSp_PFunct X) by TARSKI:def_3; reconsider h = v2 + u2 as Element of PFuncs (X,REAL) ; reconsider v2 = v2, u2 = u2 as Element of PFuncs (X,REAL) ; assume A1: ( f = v & g = u ) ; ::_thesis: f + g = v + u A2: ( dom h = (dom v2) /\ (dom u2) & ( for x being Element of X st x in dom h holds h . x = (v2 . x) + (u2 . x) ) ) by LPSPACE1:6; for x being set st x in dom h holds h . x = (f . x) + (g . x) by A1, LPSPACE1:6; then h = f + g by A1, A2, VALUED_1:def_1; hence f + g = v + u by LPSPACE1:4; ::_thesis: verum end; theorem Th30: :: LPSPACE2:30 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u let f be PartFunc of X,REAL; ::_thesis: for a being Real for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u let a be Real; ::_thesis: for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u let k be positive Real; ::_thesis: for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds a (#) f = a * u let u be VECTOR of (RLSp_LpFunct (M,k)); ::_thesis: ( f = u implies a (#) f = a * u ) reconsider u2 = u as VECTOR of (RLSp_PFunct X) by TARSKI:def_3; reconsider h = a * u2 as Element of PFuncs (X,REAL) ; assume A1: f = u ; ::_thesis: a (#) f = a * u then A2: dom h = dom f by LPSPACE1:9; then for x being set st x in dom h holds h . x = a * (f . x) by A1, LPSPACE1:9; then h = a (#) f by A2, VALUED_1:def_5; hence a (#) f = a * u by LPSPACE1:5; ::_thesis: verum end; theorem Th31: :: LPSPACE2:31 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) let k be positive Real; ::_thesis: for u being VECTOR of (RLSp_LpFunct (M,k)) st f = u holds ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) let u be VECTOR of (RLSp_LpFunct (M,k)); ::_thesis: ( f = u implies ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) ) reconsider u2 = u as VECTOR of (RLSp_PFunct X) by TARSKI:def_3; assume A1: f = u ; ::_thesis: ( u + ((- 1) * u) = (X --> 0) | (dom f) & ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) ) (- 1) * u = (- 1) * u2 by LPSPACE1:5; then A2: u + ((- 1) * u) = u2 + ((- 1) * u2) by LPSPACE1:4; hence u + ((- 1) * u) = (X --> 0) | (dom f) by A1, LPSPACE1:16; ::_thesis: ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) u + ((- 1) * u) in Lp_Functions (M,k) ; then consider v being PartFunc of X,REAL such that A3: ( v = u + ((- 1) * u) & ex ND being Element of S st ( M . (ND `) = 0 & dom v = ND & v is_measurable_on ND & (abs v) to_power k is_integrable_on M ) ) ; u in Lp_Functions (M,k) ; then ex uu1 being PartFunc of X,REAL st ( uu1 = u & ex ND being Element of S st ( M . (ND `) = 0 & dom uu1 = ND & uu1 is_measurable_on ND & (abs uu1) to_power k is_integrable_on M ) ) ; then consider ND being Element of S such that A4: ( M . (ND `) = 0 & dom f = ND & f is_measurable_on ND & (abs f) to_power k is_integrable_on M ) by A1; set g = X --> 0; A5: ( ND ` is Element of S & (ND `) ` = ND ) by MEASURE1:34; A6: X --> 0 in Lp_Functions (M,k) by Th23; v | ND = ((X --> 0) | ND) | ND by A2, A3, A4, A1, LPSPACE1:16; then v | ND = (X --> 0) | ND by FUNCT_1:51; then v a.e.= X --> 0,M by A4, A5, LPSPACE1:def_10; hence ex v, g being PartFunc of X,REAL st ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = u + ((- 1) * u) & g = X --> 0 & v a.e.= g,M ) by A3, A6; ::_thesis: verum end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func AlmostZeroLpFunctions (M,k) -> non empty Subset of (RLSp_LpFunct (M,k)) equals :: LPSPACE2:def 4 { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } ; coherence { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } is non empty Subset of (RLSp_LpFunct (M,k)) proof A1: now__::_thesis:_for_x_being_set_st_x_in__{__f_where_f_is_PartFunc_of_X,REAL_:_(_f_in_Lp_Functions_(M,k)_&_f_a.e.=_X_-->_0,M_)__}__holds_ x_in_the_carrier_of_(RLSp_LpFunct_(M,k)) let x be set ; ::_thesis: ( x in { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } implies x in the carrier of (RLSp_LpFunct (M,k)) ) assume x in { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } ; ::_thesis: x in the carrier of (RLSp_LpFunct (M,k)) then ex f being PartFunc of X,REAL st ( x = f & f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) ; hence x in the carrier of (RLSp_LpFunct (M,k)) ; ::_thesis: verum end; A2: X --> 0 a.e.= X --> 0,M by LPSPACE1:28; X --> 0 in Lp_Functions (M,k) by Th23; then X --> 0 in { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } by A2; hence { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } is non empty Subset of (RLSp_LpFunct (M,k)) by A1, TARSKI:def_3; ::_thesis: verum end; end; :: deftheorem defines AlmostZeroLpFunctions LPSPACE2:def_4_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds AlmostZeroLpFunctions (M,k) = { f where f is PartFunc of X,REAL : ( f in Lp_Functions (M,k) & f a.e.= X --> 0,M ) } ; Lm4: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( AlmostZeroLpFunctions (M,k) is add-closed & AlmostZeroLpFunctions (M,k) is multi-closed ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( AlmostZeroLpFunctions (M,k) is add-closed & AlmostZeroLpFunctions (M,k) is multi-closed ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real holds ( AlmostZeroLpFunctions (M,k) is add-closed & AlmostZeroLpFunctions (M,k) is multi-closed ) let M be sigma_Measure of S; ::_thesis: for k being positive Real holds ( AlmostZeroLpFunctions (M,k) is add-closed & AlmostZeroLpFunctions (M,k) is multi-closed ) let k be positive Real; ::_thesis: ( AlmostZeroLpFunctions (M,k) is add-closed & AlmostZeroLpFunctions (M,k) is multi-closed ) set Z = AlmostZeroLpFunctions (M,k); set V = RLSp_LpFunct (M,k); now__::_thesis:_for_v,_u_being_VECTOR_of_(RLSp_LpFunct_(M,k))_st_v_in_AlmostZeroLpFunctions_(M,k)_&_u_in_AlmostZeroLpFunctions_(M,k)_holds_ v_+_u_in_AlmostZeroLpFunctions_(M,k) let v, u be VECTOR of (RLSp_LpFunct (M,k)); ::_thesis: ( v in AlmostZeroLpFunctions (M,k) & u in AlmostZeroLpFunctions (M,k) implies v + u in AlmostZeroLpFunctions (M,k) ) assume A1: ( v in AlmostZeroLpFunctions (M,k) & u in AlmostZeroLpFunctions (M,k) ) ; ::_thesis: v + u in AlmostZeroLpFunctions (M,k) then consider v1 being PartFunc of X,REAL such that A2: ( v1 = v & v1 in Lp_Functions (M,k) & v1 a.e.= X --> 0,M ) ; consider u1 being PartFunc of X,REAL such that A3: ( u1 = u & u1 in Lp_Functions (M,k) & u1 a.e.= X --> 0,M ) by A1; A4: v + u = v1 + u1 by Th29, A2, A3; (X --> 0) + (X --> 0) = X --> 0 by LPSPACE1:33; then ( v1 + u1 in Lp_Functions (M,k) & v1 + u1 a.e.= X --> 0,M ) by A4, A2, A3, LPSPACE1:31; hence v + u in AlmostZeroLpFunctions (M,k) by A4; ::_thesis: verum end; hence AlmostZeroLpFunctions (M,k) is add-closed by IDEAL_1:def_1; ::_thesis: AlmostZeroLpFunctions (M,k) is multi-closed now__::_thesis:_for_a_being_Real for_u_being_VECTOR_of_(RLSp_LpFunct_(M,k))_st_u_in_AlmostZeroLpFunctions_(M,k)_holds_ a_*_u_in_AlmostZeroLpFunctions_(M,k) let a be Real; ::_thesis: for u being VECTOR of (RLSp_LpFunct (M,k)) st u in AlmostZeroLpFunctions (M,k) holds a * u in AlmostZeroLpFunctions (M,k) let u be VECTOR of (RLSp_LpFunct (M,k)); ::_thesis: ( u in AlmostZeroLpFunctions (M,k) implies a * u in AlmostZeroLpFunctions (M,k) ) assume u in AlmostZeroLpFunctions (M,k) ; ::_thesis: a * u in AlmostZeroLpFunctions (M,k) then consider u1 being PartFunc of X,REAL such that A5: ( u1 = u & u1 in Lp_Functions (M,k) & u1 a.e.= X --> 0,M ) ; A6: a * u = a (#) u1 by Th30, A5; a (#) (X --> 0) = X --> 0 by LPSPACE1:33; then ( a (#) u1 in Lp_Functions (M,k) & a (#) u1 a.e.= X --> 0,M ) by A6, A5, LPSPACE1:32; hence a * u in AlmostZeroLpFunctions (M,k) by A6; ::_thesis: verum end; hence AlmostZeroLpFunctions (M,k) is multi-closed by LPSPACE1:def_1; ::_thesis: verum end; registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; cluster AlmostZeroLpFunctions (M,k) -> non empty add-closed multi-closed ; coherence ( AlmostZeroLpFunctions (M,k) is add-closed & AlmostZeroLpFunctions (M,k) is multi-closed ) by Lm4; end; theorem Th32: :: LPSPACE2:32 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( 0. (RLSp_LpFunct (M,k)) = X --> 0 & 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds ( 0. (RLSp_LpFunct (M,k)) = X --> 0 & 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real holds ( 0. (RLSp_LpFunct (M,k)) = X --> 0 & 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) ) let M be sigma_Measure of S; ::_thesis: for k being positive Real holds ( 0. (RLSp_LpFunct (M,k)) = X --> 0 & 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) ) let k be positive Real; ::_thesis: ( 0. (RLSp_LpFunct (M,k)) = X --> 0 & 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) ) thus 0. (RLSp_LpFunct (M,k)) = X --> 0 by Th23, FUNCT_7:def_1; ::_thesis: 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) A1: ( X --> 0 a.e.= X --> 0,M & X --> 0 in Lp_Functions (M,k) ) by Th23, LPSPACE1:28; 0. (RLSp_LpFunct (M,k)) = 0. (RLSp_PFunct X) by Th23, FUNCT_7:def_1; hence 0. (RLSp_LpFunct (M,k)) in AlmostZeroLpFunctions (M,k) by A1; ::_thesis: verum end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func RLSp_AlmostZeroLpFunct (M,k) -> non empty RLSStruct equals :: LPSPACE2:def 5 RLSStruct(# (AlmostZeroLpFunctions (M,k)),(In ((0. (RLSp_LpFunct (M,k))),(AlmostZeroLpFunctions (M,k)))),(add| ((AlmostZeroLpFunctions (M,k)),(RLSp_LpFunct (M,k)))),(Mult_ (AlmostZeroLpFunctions (M,k))) #); coherence RLSStruct(# (AlmostZeroLpFunctions (M,k)),(In ((0. (RLSp_LpFunct (M,k))),(AlmostZeroLpFunctions (M,k)))),(add| ((AlmostZeroLpFunctions (M,k)),(RLSp_LpFunct (M,k)))),(Mult_ (AlmostZeroLpFunctions (M,k))) #) is non empty RLSStruct ; end; :: deftheorem defines RLSp_AlmostZeroLpFunct LPSPACE2:def_5_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds RLSp_AlmostZeroLpFunct (M,k) = RLSStruct(# (AlmostZeroLpFunctions (M,k)),(In ((0. (RLSp_LpFunct (M,k))),(AlmostZeroLpFunctions (M,k)))),(add| ((AlmostZeroLpFunctions (M,k)),(RLSp_LpFunct (M,k)))),(Mult_ (AlmostZeroLpFunctions (M,k))) #); registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; cluster RLSp_LpFunct (M,k) -> non empty strict Abelian add-associative right_zeroed vector-distributive scalar-distributive scalar-associative scalar-unital ; coherence ( RLSp_LpFunct (M,k) is strict & RLSp_LpFunct (M,k) is Abelian & RLSp_LpFunct (M,k) is add-associative & RLSp_LpFunct (M,k) is right_zeroed & RLSp_LpFunct (M,k) is vector-distributive & RLSp_LpFunct (M,k) is scalar-distributive & RLSp_LpFunct (M,k) is scalar-associative & RLSp_LpFunct (M,k) is scalar-unital ) ; end; theorem :: LPSPACE2:33 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = v & g = u holds f + g = v + u proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = v & g = u holds f + g = v + u let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = v & g = u holds f + g = v + u let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real for v, u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = v & g = u holds f + g = v + u let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real for v, u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = v & g = u holds f + g = v + u let k be positive Real; ::_thesis: for v, u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = v & g = u holds f + g = v + u let v, u be VECTOR of (RLSp_AlmostZeroLpFunct (M,k)); ::_thesis: ( f = v & g = u implies f + g = v + u ) reconsider v2 = v, u2 = u as VECTOR of (RLSp_LpFunct (M,k)) by TARSKI:def_3; assume A1: ( f = v & g = u ) ; ::_thesis: f + g = v + u v + u = v2 + u2 by LPSPACE1:4; hence v + u = f + g by Th29, A1; ::_thesis: verum end; theorem :: LPSPACE2:34 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for a being Real for k being positive Real for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u let f be PartFunc of X,REAL; ::_thesis: for a being Real for k being positive Real for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u let a be Real; ::_thesis: for k being positive Real for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u let k be positive Real; ::_thesis: for u being VECTOR of (RLSp_AlmostZeroLpFunct (M,k)) st f = u holds a (#) f = a * u let u be VECTOR of (RLSp_AlmostZeroLpFunct (M,k)); ::_thesis: ( f = u implies a (#) f = a * u ) reconsider u2 = u as VECTOR of (RLSp_LpFunct (M,k)) by TARSKI:def_3; assume A1: f = u ; ::_thesis: a (#) f = a * u a * u = a * u2 by LPSPACE1:5; hence a * u = a (#) f by Th30, A1; ::_thesis: verum end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let f be PartFunc of X,REAL; let k be positive Real; func a.e-eq-class_Lp (f,M,k) -> Subset of (Lp_Functions (M,k)) equals :: LPSPACE2:def 6 { h where h is PartFunc of X,REAL : ( h in Lp_Functions (M,k) & f a.e.= h,M ) } ; correctness coherence { h where h is PartFunc of X,REAL : ( h in Lp_Functions (M,k) & f a.e.= h,M ) } is Subset of (Lp_Functions (M,k)); proof now__::_thesis:_for_x_being_set_st_x_in__{__g_where_g_is_PartFunc_of_X,REAL_:_(_g_in_Lp_Functions_(M,k)_&_f_a.e.=_g,M_)__}__holds_ x_in_Lp_Functions_(M,k) let x be set ; ::_thesis: ( x in { g where g is PartFunc of X,REAL : ( g in Lp_Functions (M,k) & f a.e.= g,M ) } implies x in Lp_Functions (M,k) ) assume x in { g where g is PartFunc of X,REAL : ( g in Lp_Functions (M,k) & f a.e.= g,M ) } ; ::_thesis: x in Lp_Functions (M,k) then ex g being PartFunc of X,REAL st ( x = g & g in Lp_Functions (M,k) & f a.e.= g,M ) ; hence x in Lp_Functions (M,k) ; ::_thesis: verum end; hence { h where h is PartFunc of X,REAL : ( h in Lp_Functions (M,k) & f a.e.= h,M ) } is Subset of (Lp_Functions (M,k)) by TARSKI:def_3; ::_thesis: verum end; end; :: deftheorem defines a.e-eq-class_Lp LPSPACE2:def_6_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real holds a.e-eq-class_Lp (f,M,k) = { h where h is PartFunc of X,REAL : ( h in Lp_Functions (M,k) & f a.e.= h,M ) } ; theorem Th35: :: LPSPACE2:35 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) holds ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) implies ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) ) assume f in Lp_Functions (M,k) ; ::_thesis: ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) then ex f1 being PartFunc of X,REAL st ( f = f1 & ex E being Element of S st ( M . (E `) = 0 & dom f1 = E & f1 is_measurable_on E & (abs f1) to_power k is_integrable_on M ) ) ; hence ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) ; ::_thesis: verum end; theorem Th36: :: LPSPACE2:36 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for g, f being PartFunc of X,REAL for k being positive Real st g in Lp_Functions (M,k) & g a.e.= f,M holds g in a.e-eq-class_Lp (f,M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for g, f being PartFunc of X,REAL for k being positive Real st g in Lp_Functions (M,k) & g a.e.= f,M holds g in a.e-eq-class_Lp (f,M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for g, f being PartFunc of X,REAL for k being positive Real st g in Lp_Functions (M,k) & g a.e.= f,M holds g in a.e-eq-class_Lp (f,M,k) let M be sigma_Measure of S; ::_thesis: for g, f being PartFunc of X,REAL for k being positive Real st g in Lp_Functions (M,k) & g a.e.= f,M holds g in a.e-eq-class_Lp (f,M,k) let g, f be PartFunc of X,REAL; ::_thesis: for k being positive Real st g in Lp_Functions (M,k) & g a.e.= f,M holds g in a.e-eq-class_Lp (f,M,k) let k be positive Real; ::_thesis: ( g in Lp_Functions (M,k) & g a.e.= f,M implies g in a.e-eq-class_Lp (f,M,k) ) assume that A1: g in Lp_Functions (M,k) and A2: g a.e.= f,M ; ::_thesis: g in a.e-eq-class_Lp (f,M,k) f a.e.= g,M by A2, LPSPACE1:29; hence g in a.e-eq-class_Lp (f,M,k) by A1; ::_thesis: verum end; theorem Th37: :: LPSPACE2:37 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & g in a.e-eq-class_Lp (f,M,k) holds ( g a.e.= f,M & f in Lp_Functions (M,k) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & g in a.e-eq-class_Lp (f,M,k) holds ( g a.e.= f,M & f in Lp_Functions (M,k) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & g in a.e-eq-class_Lp (f,M,k) holds ( g a.e.= f,M & f in Lp_Functions (M,k) ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & g in a.e-eq-class_Lp (f,M,k) holds ( g a.e.= f,M & f in Lp_Functions (M,k) ) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & g in a.e-eq-class_Lp (f,M,k) holds ( g a.e.= f,M & f in Lp_Functions (M,k) ) let k be positive Real; ::_thesis: ( ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & g in a.e-eq-class_Lp (f,M,k) implies ( g a.e.= f,M & f in Lp_Functions (M,k) ) ) assume that A1: ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) and A2: g in a.e-eq-class_Lp (f,M,k) ; ::_thesis: ( g a.e.= f,M & f in Lp_Functions (M,k) ) A3: ex r being PartFunc of X,REAL st ( g = r & r in Lp_Functions (M,k) & f a.e.= r,M ) by A2; hence g a.e.= f,M by LPSPACE1:29; ::_thesis: f in Lp_Functions (M,k) g in Lp_Functions (M,k) by A2; then consider g1 being PartFunc of X,REAL such that A4: ( g = g1 & ex E being Element of S st ( M . (E `) = 0 & dom g1 = E & g1 is_measurable_on E & (abs g1) to_power k is_integrable_on M ) ) ; consider Eh being Element of S such that A5: ( M . (Eh `) = 0 & dom g = Eh & g is_measurable_on Eh & (abs g) to_power k is_integrable_on M ) by A4; reconsider ND = Eh ` as Element of S by MEASURE1:34; ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E & (abs f) to_power k is_integrable_on M ) proof set AFK = (abs f) to_power k; set AGK = (abs g) to_power k; consider Ef being Element of S such that A6: ( M . (Ef `) = 0 & Ef = dom f & f is_measurable_on Ef ) by A1; take Ef ; ::_thesis: ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) consider EE being Element of S such that A7: ( M . EE = 0 & g | (EE `) = f | (EE `) ) by A3, LPSPACE1:def_10; reconsider E1 = ND \/ EE as Element of S ; EE c= E1 by XBOOLE_1:7; then E1 ` c= EE ` by SUBSET_1:12; then A8: ( f | (E1 `) = (f | (EE `)) | (E1 `) & g | (E1 `) = (g | (EE `)) | (E1 `) ) by FUNCT_1:51; A9: dom (abs f) = Ef by A6, VALUED_1:def_11; then dom ((abs f) to_power k) = Ef by MESFUN6C:def_4; then A10: ( dom (max+ (R_EAL ((abs f) to_power k))) = Ef & dom (max- (R_EAL ((abs f) to_power k))) = Ef ) by MESFUNC2:def_2, MESFUNC2:def_3; abs f is_measurable_on Ef by A6, MESFUNC6:48; then (abs f) to_power k is_measurable_on Ef by A9, MESFUN6C:29; then A11: ( Ef = dom (R_EAL ((abs f) to_power k)) & R_EAL ((abs f) to_power k) is_measurable_on Ef ) by A9, MESFUN6C:def_4, MESFUNC6:def_1; then A12: ( max+ (R_EAL ((abs f) to_power k)) is_measurable_on Ef & max- (R_EAL ((abs f) to_power k)) is_measurable_on Ef ) by MESFUNC2:25, MESFUNC2:26; ( ( for x being Element of X holds 0. <= (max+ (R_EAL ((abs f) to_power k))) . x ) & ( for x being Element of X holds 0. <= (max- (R_EAL ((abs f) to_power k))) . x ) ) by MESFUNC2:12, MESFUNC2:13; then A13: ( max+ (R_EAL ((abs f) to_power k)) is nonnegative & max- (R_EAL ((abs f) to_power k)) is nonnegative ) by SUPINF_2:39; A14: Ef = (Ef /\ E1) \/ (Ef \ E1) by XBOOLE_1:51; reconsider E0 = Ef /\ E1 as Element of S ; reconsider E2 = Ef \ E1 as Element of S ; ( max+ (R_EAL ((abs f) to_power k)) = (max+ (R_EAL ((abs f) to_power k))) | (dom (max+ (R_EAL ((abs f) to_power k)))) & max- (R_EAL ((abs f) to_power k)) = (max- (R_EAL ((abs f) to_power k))) | (dom (max- (R_EAL ((abs f) to_power k)))) ) by RELAT_1:69; then A15: ( integral+ (M,(max+ (R_EAL ((abs f) to_power k)))) = (integral+ (M,((max+ (R_EAL ((abs f) to_power k))) | E0))) + (integral+ (M,((max+ (R_EAL ((abs f) to_power k))) | E2))) & integral+ (M,(max- (R_EAL ((abs f) to_power k)))) = (integral+ (M,((max- (R_EAL ((abs f) to_power k))) | E0))) + (integral+ (M,((max- (R_EAL ((abs f) to_power k))) | E2))) ) by A10, A12, A13, A14, MESFUNC5:81, XBOOLE_1:89; A16: ( integral+ (M,((max+ (R_EAL ((abs f) to_power k))) | E0)) >= 0 & integral+ (M,((max- (R_EAL ((abs f) to_power k))) | E0)) >= 0 ) by A12, A13, A10, MESFUNC5:80; ( ND is measure_zero of M & EE is measure_zero of M ) by A5, A7, MEASURE1:def_7; then E1 is measure_zero of M by MEASURE1:37; then M . E1 = 0 by MEASURE1:def_7; then ( integral+ (M,((max+ (R_EAL ((abs f) to_power k))) | E1)) = 0 & integral+ (M,((max- (R_EAL ((abs f) to_power k))) | E1)) = 0 ) by A10, A12, A13, MESFUNC5:82; then ( integral+ (M,((max+ (R_EAL ((abs f) to_power k))) | E0)) = 0 & integral+ (M,((max- (R_EAL ((abs f) to_power k))) | E0)) = 0 ) by A10, A12, A13, A16, MESFUNC5:83, XBOOLE_1:17; then A17: ( integral+ (M,(max+ (R_EAL ((abs f) to_power k)))) = integral+ (M,((max+ (R_EAL ((abs f) to_power k))) | E2)) & integral+ (M,(max- (R_EAL ((abs f) to_power k)))) = integral+ (M,((max- (R_EAL ((abs f) to_power k))) | E2)) ) by A15, XXREAL_3:4; Ef \ E1 = Ef /\ (E1 `) by SUBSET_1:13; then A18: E2 c= E1 ` by XBOOLE_1:17; then f | E2 = (g | (E1 `)) | E2 by A7, A8, FUNCT_1:51; then A19: f | E2 = g | E2 by A18, FUNCT_1:51; A20: ( (abs f) | E2 = abs (f | E2) & (abs g) | E2 = abs (g | E2) ) by RFUNCT_1:46; A21: ( ((abs f) | E2) to_power k = ((abs f) to_power k) | E2 & ((abs g) | E2) to_power k = ((abs g) to_power k) | E2 ) by Th20; A22: ( (max+ (R_EAL ((abs f) to_power k))) | E2 = max+ ((R_EAL ((abs f) to_power k)) | E2) & (max+ (R_EAL ((abs g) to_power k))) | E2 = max+ ((R_EAL ((abs g) to_power k)) | E2) & (max- (R_EAL ((abs f) to_power k))) | E2 = max- ((R_EAL ((abs f) to_power k)) | E2) & (max- (R_EAL ((abs g) to_power k))) | E2 = max- ((R_EAL ((abs g) to_power k)) | E2) ) by MESFUNC5:28; A23: R_EAL ((abs g) to_power k) is_integrable_on M by A5, MESFUNC6:def_4; then A24: ( integral+ (M,(max+ (R_EAL ((abs g) to_power k)))) < +infty & integral+ (M,(max- (R_EAL ((abs g) to_power k)))) < +infty ) by MESFUNC5:def_17; ( integral+ (M,(max+ ((R_EAL ((abs g) to_power k)) | E2))) <= integral+ (M,(max+ (R_EAL ((abs g) to_power k)))) & integral+ (M,(max- ((R_EAL ((abs g) to_power k)) | E2))) <= integral+ (M,(max- (R_EAL ((abs g) to_power k)))) ) by A23, MESFUNC5:97; then ( integral+ (M,(max+ (R_EAL ((abs f) to_power k)))) < +infty & integral+ (M,(max- (R_EAL ((abs f) to_power k)))) < +infty ) by A17, A19, A20, A21, A22, A24, XXREAL_0:2; then R_EAL ((abs f) to_power k) is_integrable_on M by A11, MESFUNC5:def_17; hence ( M . (Ef `) = 0 & dom f = Ef & f is_measurable_on Ef & (abs f) to_power k is_integrable_on M ) by A6, MESFUNC6:def_4; ::_thesis: verum end; hence f in Lp_Functions (M,k) ; ::_thesis: verum end; theorem Th38: :: LPSPACE2:38 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds f in a.e-eq-class_Lp (f,M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds f in a.e-eq-class_Lp (f,M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds f in a.e-eq-class_Lp (f,M,k) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds f in a.e-eq-class_Lp (f,M,k) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) holds f in a.e-eq-class_Lp (f,M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) implies f in a.e-eq-class_Lp (f,M,k) ) assume A1: f in Lp_Functions (M,k) ; ::_thesis: f in a.e-eq-class_Lp (f,M,k) f a.e.= f,M by LPSPACE1:28; hence f in a.e-eq-class_Lp (f,M,k) by A1; ::_thesis: verum end; theorem Th39: :: LPSPACE2:39 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for g, f being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) <> {} & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for g, f being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) <> {} & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for g, f being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) <> {} & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let M be sigma_Measure of S; ::_thesis: for g, f being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) <> {} & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let g, f be PartFunc of X,REAL; ::_thesis: for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) <> {} & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let k be positive Real; ::_thesis: ( ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) <> {} & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) implies f a.e.= g,M ) assume that A1: ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) and A2: a.e-eq-class_Lp (f,M,k) <> {} and A3: a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ; ::_thesis: f a.e.= g,M consider x being set such that A4: x in a.e-eq-class_Lp (f,M,k) by A2, XBOOLE_0:def_1; consider r being PartFunc of X,REAL such that A5: ( x = r & r in Lp_Functions (M,k) & f a.e.= r,M ) by A4; r a.e.= g,M by A1, A3, A4, A5, Th37; hence f a.e.= g,M by A5, LPSPACE1:30; ::_thesis: verum end; theorem :: LPSPACE2:40 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds f a.e.= g,M let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) implies f a.e.= g,M ) assume that A1: f in Lp_Functions (M,k) and A2: ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) and A3: a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ; ::_thesis: f a.e.= g,M not a.e-eq-class_Lp (f,M,k) is empty by A1, Th38; hence f a.e.= g,M by A2, A3, Th39; ::_thesis: verum end; theorem Th41: :: LPSPACE2:41 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f a.e.= g,M holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f a.e.= g,M holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f a.e.= g,M holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st f a.e.= g,M holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st f a.e.= g,M holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let k be positive Real; ::_thesis: ( f a.e.= g,M implies a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ) assume A1: f a.e.= g,M ; ::_thesis: a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) now__::_thesis:_for_x_being_set_st_x_in_a.e-eq-class_Lp_(f,M,k)_holds_ x_in_a.e-eq-class_Lp_(g,M,k) let x be set ; ::_thesis: ( x in a.e-eq-class_Lp (f,M,k) implies x in a.e-eq-class_Lp (g,M,k) ) assume x in a.e-eq-class_Lp (f,M,k) ; ::_thesis: x in a.e-eq-class_Lp (g,M,k) then consider r being PartFunc of X,REAL such that A2: ( x = r & r in Lp_Functions (M,k) & f a.e.= r,M ) ; r a.e.= f,M by A2, LPSPACE1:29; then r a.e.= g,M by A1, LPSPACE1:30; then g a.e.= r,M by LPSPACE1:29; hence x in a.e-eq-class_Lp (g,M,k) by A2; ::_thesis: verum end; then A3: a.e-eq-class_Lp (f,M,k) c= a.e-eq-class_Lp (g,M,k) by TARSKI:def_3; now__::_thesis:_for_x_being_set_st_x_in_a.e-eq-class_Lp_(g,M,k)_holds_ x_in_a.e-eq-class_Lp_(f,M,k) let x be set ; ::_thesis: ( x in a.e-eq-class_Lp (g,M,k) implies x in a.e-eq-class_Lp (f,M,k) ) assume x in a.e-eq-class_Lp (g,M,k) ; ::_thesis: x in a.e-eq-class_Lp (f,M,k) then consider r being PartFunc of X,REAL such that A4: ( x = r & r in Lp_Functions (M,k) & g a.e.= r,M ) ; ( r a.e.= g,M & g a.e.= f,M ) by A1, A4, LPSPACE1:29; then r a.e.= f,M by LPSPACE1:30; then f a.e.= r,M by LPSPACE1:29; hence x in a.e-eq-class_Lp (f,M,k) by A4; ::_thesis: verum end; then a.e-eq-class_Lp (g,M,k) c= a.e-eq-class_Lp (f,M,k) by TARSKI:def_3; hence a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) by A3, XBOOLE_0:def_10; ::_thesis: verum end; theorem Th42: :: LPSPACE2:42 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f a.e.= g,M holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) by Th41; theorem :: LPSPACE2:43 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in a.e-eq-class_Lp (f,M,k) holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in a.e-eq-class_Lp (f,M,k) holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in a.e-eq-class_Lp (f,M,k) holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in a.e-eq-class_Lp (f,M,k) holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & g in a.e-eq-class_Lp (f,M,k) holds a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & g in a.e-eq-class_Lp (f,M,k) implies a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ) assume that A1: f in Lp_Functions (M,k) and A2: g in a.e-eq-class_Lp (f,M,k) ; ::_thesis: a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) by A1, Th35; hence a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) by Th41, A2, Th37; ::_thesis: verum end; theorem :: LPSPACE2:44 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let M be sigma_Measure of S; ::_thesis: for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let f, f1, g, g1 be PartFunc of X,REAL; ::_thesis: for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let k be positive Real; ::_thesis: ( ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) implies a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) ) assume ( ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom f1 & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & E = dom g1 & g1 is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & not a.e-eq-class_Lp (g,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) ) ; ::_thesis: a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) then ( f a.e.= f1,M & g a.e.= g1,M ) by Th39; hence a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) by Th41, LPSPACE1:31; ::_thesis: verum end; theorem Th45: :: LPSPACE2:45 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & f1 in Lp_Functions (M,k) & g in Lp_Functions (M,k) & g1 in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & f1 in Lp_Functions (M,k) & g in Lp_Functions (M,k) & g1 in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & f1 in Lp_Functions (M,k) & g in Lp_Functions (M,k) & g1 in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let M be sigma_Measure of S; ::_thesis: for f, f1, g, g1 being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & f1 in Lp_Functions (M,k) & g in Lp_Functions (M,k) & g1 in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let f, f1, g, g1 be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & f1 in Lp_Functions (M,k) & g in Lp_Functions (M,k) & g1 in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) holds a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & f1 in Lp_Functions (M,k) & g in Lp_Functions (M,k) & g1 in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) implies a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) ) assume that A1: f in Lp_Functions (M,k) and A2: f1 in Lp_Functions (M,k) and A3: g in Lp_Functions (M,k) and A4: g1 in Lp_Functions (M,k) and A5: ( a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (f1,M,k) & a.e-eq-class_Lp (g,M,k) = a.e-eq-class_Lp (g1,M,k) ) ; ::_thesis: a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) A6: ( ex E being Element of S st ( M . (E `) = 0 & dom f1 = E & f1 is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g1 = E & g1 is_measurable_on E ) ) by A2, A4, Th35; ( f in a.e-eq-class_Lp (f,M,k) & g in a.e-eq-class_Lp (g,M,k) ) by A1, A3, Th38; then ( f a.e.= f1,M & g a.e.= g1,M ) by A5, A6, Th37; hence a.e-eq-class_Lp ((f + g),M,k) = a.e-eq-class_Lp ((f1 + g1),M,k) by Th41, LPSPACE1:31; ::_thesis: verum end; theorem :: LPSPACE2:46 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for a being Real for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let f, g be PartFunc of X,REAL; ::_thesis: for a being Real for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let a be Real; ::_thesis: for k being positive Real st ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let k be positive Real; ::_thesis: ( ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) implies a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) ) assume ( ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) & not a.e-eq-class_Lp (f,M,k) is empty & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ) ; ::_thesis: a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) then a (#) f a.e.= a (#) g,M by Th39, LPSPACE1:32; hence a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) by Th41; ::_thesis: verum end; theorem Th47: :: LPSPACE2:47 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for a being Real for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let f, g be PartFunc of X,REAL; ::_thesis: for a being Real for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let a be Real; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) holds a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) implies a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) ) assume A1: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & a.e-eq-class_Lp (f,M,k) = a.e-eq-class_Lp (g,M,k) ) ; ::_thesis: a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) then A2: ( ex E being Element of S st ( M . (E `) = 0 & dom f = E & f is_measurable_on E ) & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) ) by Th35; f in a.e-eq-class_Lp (g,M,k) by A1, Th38; then ( f a.e.= g,M & a (#) f in Lp_Functions (M,k) & a (#) g in Lp_Functions (M,k) ) by A2, Th37, Th26; hence a.e-eq-class_Lp ((a (#) f),M,k) = a.e-eq-class_Lp ((a (#) g),M,k) by Th42, LPSPACE1:32; ::_thesis: verum end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func CosetSet (M,k) -> non empty Subset-Family of (Lp_Functions (M,k)) equals :: LPSPACE2:def 7 { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } ; correctness coherence { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } is non empty Subset-Family of (Lp_Functions (M,k)); proof set C = { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } ; A1: { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } c= bool (Lp_Functions (M,k)) proof let x be set ; :: according to TARSKI:def_3 ::_thesis: ( not x in { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } or x in bool (Lp_Functions (M,k)) ) assume x in { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } ; ::_thesis: x in bool (Lp_Functions (M,k)) then ex f being PartFunc of X,REAL st ( a.e-eq-class_Lp (f,M,k) = x & f in Lp_Functions (M,k) ) ; hence x in bool (Lp_Functions (M,k)) ; ::_thesis: verum end; X --> 0 in Lp_Functions (M,k) by Th23; then a.e-eq-class_Lp ((X --> 0),M,k) in { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } ; hence { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } is non empty Subset-Family of (Lp_Functions (M,k)) by A1; ::_thesis: verum end; end; :: deftheorem defines CosetSet LPSPACE2:def_7_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds CosetSet (M,k) = { (a.e-eq-class_Lp (f,M,k)) where f is PartFunc of X,REAL : f in Lp_Functions (M,k) } ; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func addCoset (M,k) -> BinOp of (CosetSet (M,k)) means :Def8: :: LPSPACE2:def 8 for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds it . (A,B) = a.e-eq-class_Lp ((a + b),M,k); existence ex b1 being BinOp of (CosetSet (M,k)) st for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds b1 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) proof set C = CosetSet (M,k); defpred S1[ set , set , set ] means for a, b being PartFunc of X,REAL st a in $1 & b in $2 holds $3 = a.e-eq-class_Lp ((a + b),M,k); A1: now__::_thesis:_for_A,_B_being_Element_of_CosetSet_(M,k)_ex_z_being_Element_of_CosetSet_(M,k)_st_S1[A,B,z] let A, B be Element of CosetSet (M,k); ::_thesis: ex z being Element of CosetSet (M,k) st S1[A,B,z] A in CosetSet (M,k) ; then consider a being PartFunc of X,REAL such that A2: ( A = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A3: ex E being Element of S st ( M . (E `) = 0 & dom a = E & a is_measurable_on E ) by A2, Th35; B in CosetSet (M,k) ; then consider b being PartFunc of X,REAL such that A4: ( B = a.e-eq-class_Lp (b,M,k) & b in Lp_Functions (M,k) ) ; A5: ex E being Element of S st ( M . (E `) = 0 & dom b = E & b is_measurable_on E ) by A4, Th35; set z = a.e-eq-class_Lp ((a + b),M,k); a + b in Lp_Functions (M,k) by Th25, A2, A4; then a.e-eq-class_Lp ((a + b),M,k) in CosetSet (M,k) ; then reconsider z = a.e-eq-class_Lp ((a + b),M,k) as Element of CosetSet (M,k) ; take z = z; ::_thesis: S1[A,B,z] now__::_thesis:_for_a1,_b1_being_PartFunc_of_X,REAL_st_a1_in_A_&_b1_in_B_holds_ z_=_a.e-eq-class_Lp_((a1_+_b1),M,k) let a1, b1 be PartFunc of X,REAL; ::_thesis: ( a1 in A & b1 in B implies z = a.e-eq-class_Lp ((a1 + b1),M,k) ) assume ( a1 in A & b1 in B ) ; ::_thesis: z = a.e-eq-class_Lp ((a1 + b1),M,k) then ( a1 a.e.= a,M & b1 a.e.= b,M ) by A2, A3, A4, A5, Th37; hence z = a.e-eq-class_Lp ((a1 + b1),M,k) by Th42, LPSPACE1:31; ::_thesis: verum end; hence S1[A,B,z] ; ::_thesis: verum end; consider f being Function of [:(CosetSet (M,k)),(CosetSet (M,k)):],(CosetSet (M,k)) such that A6: for A, B being Element of CosetSet (M,k) holds S1[A,B,f . (A,B)] from BINOP_1:sch_3(A1); reconsider f = f as BinOp of (CosetSet (M,k)) ; take f ; ::_thesis: for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds f . (A,B) = a.e-eq-class_Lp ((a + b),M,k) let A, B be Element of CosetSet (M,k); ::_thesis: for a, b being PartFunc of X,REAL st a in A & b in B holds f . (A,B) = a.e-eq-class_Lp ((a + b),M,k) let a, b be PartFunc of X,REAL; ::_thesis: ( a in A & b in B implies f . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ) assume ( a in A & b in B ) ; ::_thesis: f . (A,B) = a.e-eq-class_Lp ((a + b),M,k) hence f . (A,B) = a.e-eq-class_Lp ((a + b),M,k) by A6; ::_thesis: verum end; uniqueness for b1, b2 being BinOp of (CosetSet (M,k)) st ( for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds b1 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ) & ( for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds b2 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ) holds b1 = b2 proof let f1, f2 be BinOp of (CosetSet (M,k)); ::_thesis: ( ( for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds f1 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ) & ( for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds f2 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ) implies f1 = f2 ) assume that A7: for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds f1 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) and A8: for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds f2 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ; ::_thesis: f1 = f2 now__::_thesis:_for_A,_B_being_Element_of_CosetSet_(M,k)_holds_f1_._(A,B)_=_f2_._(A,B) let A, B be Element of CosetSet (M,k); ::_thesis: f1 . (A,B) = f2 . (A,B) A in CosetSet (M,k) ; then consider a1 being PartFunc of X,REAL such that A9: ( A = a.e-eq-class_Lp (a1,M,k) & a1 in Lp_Functions (M,k) ) ; B in CosetSet (M,k) ; then consider b1 being PartFunc of X,REAL such that A10: ( B = a.e-eq-class_Lp (b1,M,k) & b1 in Lp_Functions (M,k) ) ; A11: ( a1 in A & b1 in B ) by A9, A10, Th38; then f1 . (A,B) = a.e-eq-class_Lp ((a1 + b1),M,k) by A7; hence f1 . (A,B) = f2 . (A,B) by A8, A11; ::_thesis: verum end; hence f1 = f2 by BINOP_1:2; ::_thesis: verum end; end; :: deftheorem Def8 defines addCoset LPSPACE2:def_8_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for b5 being BinOp of (CosetSet (M,k)) holds ( b5 = addCoset (M,k) iff for A, B being Element of CosetSet (M,k) for a, b being PartFunc of X,REAL st a in A & b in B holds b5 . (A,B) = a.e-eq-class_Lp ((a + b),M,k) ); definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func zeroCoset (M,k) -> Element of CosetSet (M,k) equals :: LPSPACE2:def 9 a.e-eq-class_Lp ((X --> 0),M,k); correctness coherence a.e-eq-class_Lp ((X --> 0),M,k) is Element of CosetSet (M,k); proof X --> 0 in Lp_Functions (M,k) by Th23; then a.e-eq-class_Lp ((X --> 0),M,k) in CosetSet (M,k) ; hence a.e-eq-class_Lp ((X --> 0),M,k) is Element of CosetSet (M,k) ; ::_thesis: verum end; end; :: deftheorem defines zeroCoset LPSPACE2:def_9_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds zeroCoset (M,k) = a.e-eq-class_Lp ((X --> 0),M,k); definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func lmultCoset (M,k) -> Function of [:REAL,(CosetSet (M,k)):],(CosetSet (M,k)) means :Def10: :: LPSPACE2:def 10 for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds it . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k); existence ex b1 being Function of [:REAL,(CosetSet (M,k)):],(CosetSet (M,k)) st for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds b1 . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) proof set C = CosetSet (M,k); defpred S1[ Element of REAL , set , set ] means for f being PartFunc of X,REAL st f in $2 holds $3 = a.e-eq-class_Lp (($1 (#) f),M,k); A1: now__::_thesis:_for_z_being_Element_of_REAL_ for_A_being_Element_of_CosetSet_(M,k)_ex_c_being_Element_of_CosetSet_(M,k)_st_S1[z,A,c] let z be Element of REAL ; ::_thesis: for A being Element of CosetSet (M,k) ex c being Element of CosetSet (M,k) st S1[z,A,c] let A be Element of CosetSet (M,k); ::_thesis: ex c being Element of CosetSet (M,k) st S1[z,A,c] A in CosetSet (M,k) ; then consider a being PartFunc of X,REAL such that A2: ( A = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A3: ex E being Element of S st ( M . (E `) = 0 & E = dom a & a is_measurable_on E ) by A2, Th35; set c = a.e-eq-class_Lp ((z (#) a),M,k); z (#) a in Lp_Functions (M,k) by Th26, A2; then a.e-eq-class_Lp ((z (#) a),M,k) in CosetSet (M,k) ; then reconsider c = a.e-eq-class_Lp ((z (#) a),M,k) as Element of CosetSet (M,k) ; take c = c; ::_thesis: S1[z,A,c] now__::_thesis:_for_a1_being_PartFunc_of_X,REAL_st_a1_in_A_holds_ c_=_a.e-eq-class_Lp_((z_(#)_a1),M,k) let a1 be PartFunc of X,REAL; ::_thesis: ( a1 in A implies c = a.e-eq-class_Lp ((z (#) a1),M,k) ) assume a1 in A ; ::_thesis: c = a.e-eq-class_Lp ((z (#) a1),M,k) then z (#) a1 a.e.= z (#) a,M by A2, A3, Th37, LPSPACE1:32; hence c = a.e-eq-class_Lp ((z (#) a1),M,k) by Th42; ::_thesis: verum end; hence S1[z,A,c] ; ::_thesis: verum end; consider f being Function of [:REAL,(CosetSet (M,k)):],(CosetSet (M,k)) such that A4: for z being Element of REAL for A being Element of CosetSet (M,k) holds S1[z,A,f . (z,A)] from BINOP_1:sch_3(A1); take f ; ::_thesis: for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds f . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) let z be Element of REAL ; ::_thesis: for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds f . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) let A be Element of CosetSet (M,k); ::_thesis: for f being PartFunc of X,REAL st f in A holds f . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) let a be PartFunc of X,REAL; ::_thesis: ( a in A implies f . (z,A) = a.e-eq-class_Lp ((z (#) a),M,k) ) assume a in A ; ::_thesis: f . (z,A) = a.e-eq-class_Lp ((z (#) a),M,k) hence f . (z,A) = a.e-eq-class_Lp ((z (#) a),M,k) by A4; ::_thesis: verum end; uniqueness for b1, b2 being Function of [:REAL,(CosetSet (M,k)):],(CosetSet (M,k)) st ( for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds b1 . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) ) & ( for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds b2 . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) ) holds b1 = b2 proof set C = CosetSet (M,k); let f1, f2 be Function of [:REAL,(CosetSet (M,k)):],(CosetSet (M,k)); ::_thesis: ( ( for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds f1 . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) ) & ( for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds f2 . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) ) implies f1 = f2 ) assume that A5: for z being Element of REAL for A being Element of CosetSet (M,k) for a being PartFunc of X,REAL st a in A holds f1 . (z,A) = a.e-eq-class_Lp ((z (#) a),M,k) and A6: for z being Element of REAL for A being Element of CosetSet (M,k) for a being PartFunc of X,REAL st a in A holds f2 . (z,A) = a.e-eq-class_Lp ((z (#) a),M,k) ; ::_thesis: f1 = f2 now__::_thesis:_for_z_being_Element_of_REAL_ for_A_being_Element_of_CosetSet_(M,k)_holds_f1_._(z,A)_=_f2_._(z,A) let z be Element of REAL ; ::_thesis: for A being Element of CosetSet (M,k) holds f1 . (z,A) = f2 . (z,A) let A be Element of CosetSet (M,k); ::_thesis: f1 . (z,A) = f2 . (z,A) A in CosetSet (M,k) ; then consider a1 being PartFunc of X,REAL such that A7: ( A = a.e-eq-class_Lp (a1,M,k) & a1 in Lp_Functions (M,k) ) ; thus f1 . (z,A) = a.e-eq-class_Lp ((z (#) a1),M,k) by A5, A7, Th38 .= f2 . (z,A) by A6, A7, Th38 ; ::_thesis: verum end; hence f1 = f2 by BINOP_1:2; ::_thesis: verum end; end; :: deftheorem Def10 defines lmultCoset LPSPACE2:def_10_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for b5 being Function of [:REAL,(CosetSet (M,k)):],(CosetSet (M,k)) holds ( b5 = lmultCoset (M,k) iff for z being Element of REAL for A being Element of CosetSet (M,k) for f being PartFunc of X,REAL st f in A holds b5 . (z,A) = a.e-eq-class_Lp ((z (#) f),M,k) ); definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func Pre-Lp-Space (M,k) -> strict RLSStruct means :Def11: :: LPSPACE2:def 11 ( the carrier of it = CosetSet (M,k) & the addF of it = addCoset (M,k) & 0. it = zeroCoset (M,k) & the Mult of it = lmultCoset (M,k) ); existence ex b1 being strict RLSStruct st ( the carrier of b1 = CosetSet (M,k) & the addF of b1 = addCoset (M,k) & 0. b1 = zeroCoset (M,k) & the Mult of b1 = lmultCoset (M,k) ) proof take RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) ; ::_thesis: ( the carrier of RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = CosetSet (M,k) & the addF of RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = addCoset (M,k) & 0. RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = zeroCoset (M,k) & the Mult of RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = lmultCoset (M,k) ) thus ( the carrier of RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = CosetSet (M,k) & the addF of RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = addCoset (M,k) & 0. RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = zeroCoset (M,k) & the Mult of RLSStruct(# (CosetSet (M,k)),(zeroCoset (M,k)),(addCoset (M,k)),(lmultCoset (M,k)) #) = lmultCoset (M,k) ) ; ::_thesis: verum end; uniqueness for b1, b2 being strict RLSStruct st the carrier of b1 = CosetSet (M,k) & the addF of b1 = addCoset (M,k) & 0. b1 = zeroCoset (M,k) & the Mult of b1 = lmultCoset (M,k) & the carrier of b2 = CosetSet (M,k) & the addF of b2 = addCoset (M,k) & 0. b2 = zeroCoset (M,k) & the Mult of b2 = lmultCoset (M,k) holds b1 = b2 ; end; :: deftheorem Def11 defines Pre-Lp-Space LPSPACE2:def_11_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for b5 being strict RLSStruct holds ( b5 = Pre-Lp-Space (M,k) iff ( the carrier of b5 = CosetSet (M,k) & the addF of b5 = addCoset (M,k) & 0. b5 = zeroCoset (M,k) & the Mult of b5 = lmultCoset (M,k) ) ); registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; cluster Pre-Lp-Space (M,k) -> non empty strict ; coherence not Pre-Lp-Space (M,k) is empty proof the carrier of (Pre-Lp-Space (M,k)) = CosetSet (M,k) by Def11; hence not Pre-Lp-Space (M,k) is empty ; ::_thesis: verum end; end; registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; cluster Pre-Lp-Space (M,k) -> right_complementable strict Abelian add-associative right_zeroed vector-distributive scalar-distributive scalar-associative scalar-unital ; coherence ( Pre-Lp-Space (M,k) is Abelian & Pre-Lp-Space (M,k) is add-associative & Pre-Lp-Space (M,k) is right_zeroed & Pre-Lp-Space (M,k) is right_complementable & Pre-Lp-Space (M,k) is vector-distributive & Pre-Lp-Space (M,k) is scalar-distributive & Pre-Lp-Space (M,k) is scalar-associative & Pre-Lp-Space (M,k) is scalar-unital ) proof set C = CosetSet (M,k); set aC = addCoset (M,k); set lC = lmultCoset (M,k); set A = Pre-Lp-Space (M,k); A1: ( the carrier of (Pre-Lp-Space (M,k)) = CosetSet (M,k) & the addF of (Pre-Lp-Space (M,k)) = addCoset (M,k) & 0. (Pre-Lp-Space (M,k)) = zeroCoset (M,k) & the Mult of (Pre-Lp-Space (M,k)) = lmultCoset (M,k) ) by Def11; thus Pre-Lp-Space (M,k) is Abelian ::_thesis: ( Pre-Lp-Space (M,k) is add-associative & Pre-Lp-Space (M,k) is right_zeroed & Pre-Lp-Space (M,k) is right_complementable & Pre-Lp-Space (M,k) is vector-distributive & Pre-Lp-Space (M,k) is scalar-distributive & Pre-Lp-Space (M,k) is scalar-associative & Pre-Lp-Space (M,k) is scalar-unital ) proof let A1, A2 be Element of (Pre-Lp-Space (M,k)); :: according to RLVECT_1:def_2 ::_thesis: A1 + A2 = A2 + A1 A1 in CosetSet (M,k) by A1; then consider a being PartFunc of X,REAL such that A2: ( A1 = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A2 in CosetSet (M,k) by A1; then consider b being PartFunc of X,REAL such that A3: ( A2 = a.e-eq-class_Lp (b,M,k) & b in Lp_Functions (M,k) ) ; A4: ( a in A1 & b in A2 ) by A2, A3, Th38; then A1 + A2 = a.e-eq-class_Lp ((a + b),M,k) by A1, Def8; hence A1 + A2 = A2 + A1 by A1, A4, Def8; ::_thesis: verum end; thus Pre-Lp-Space (M,k) is add-associative ::_thesis: ( Pre-Lp-Space (M,k) is right_zeroed & Pre-Lp-Space (M,k) is right_complementable & Pre-Lp-Space (M,k) is vector-distributive & Pre-Lp-Space (M,k) is scalar-distributive & Pre-Lp-Space (M,k) is scalar-associative & Pre-Lp-Space (M,k) is scalar-unital ) proof let A1, A2, A3 be Element of (Pre-Lp-Space (M,k)); :: according to RLVECT_1:def_3 ::_thesis: (A1 + A2) + A3 = A1 + (A2 + A3) A1 in CosetSet (M,k) by A1; then consider a being PartFunc of X,REAL such that A5: ( A1 = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A2 in CosetSet (M,k) by A1; then consider b being PartFunc of X,REAL such that A6: ( A2 = a.e-eq-class_Lp (b,M,k) & b in Lp_Functions (M,k) ) ; A3 in CosetSet (M,k) by A1; then consider c being PartFunc of X,REAL such that A7: ( A3 = a.e-eq-class_Lp (c,M,k) & c in Lp_Functions (M,k) ) ; A8: ( a in A1 & b in A2 & c in A3 ) by A5, A6, A7, Th38; then ( (addCoset (M,k)) . (A1,A2) = a.e-eq-class_Lp ((a + b),M,k) & (addCoset (M,k)) . (A2,A3) = a.e-eq-class_Lp ((b + c),M,k) ) by A1, Def8; then A9: ( a + b in A1 + A2 & b + c in A2 + A3 ) by A1, Th38, Th25, A5, A6, A7; reconsider a1 = a, b1 = b, c1 = c as VECTOR of (RLSp_LpFunct (M,k)) by A5, A6, A7; A10: ( a + b = a1 + b1 & b + c = b1 + c1 ) by Th29; then a + (b + c) = a1 + (b1 + c1) by Th29; then a + (b + c) = (a1 + b1) + c1 by RLVECT_1:def_3; then a + (b + c) = (a + b) + c by A10, Th29; then (A1 + A2) + A3 = a.e-eq-class_Lp ((a + (b + c)),M,k) by A8, A9, Def8, A1; hence (A1 + A2) + A3 = A1 + (A2 + A3) by A8, A9, Def8, A1; ::_thesis: verum end; thus Pre-Lp-Space (M,k) is right_zeroed ::_thesis: ( Pre-Lp-Space (M,k) is right_complementable & Pre-Lp-Space (M,k) is vector-distributive & Pre-Lp-Space (M,k) is scalar-distributive & Pre-Lp-Space (M,k) is scalar-associative & Pre-Lp-Space (M,k) is scalar-unital ) proof let A1 be Element of (Pre-Lp-Space (M,k)); :: according to RLVECT_1:def_4 ::_thesis: A1 + (0. (Pre-Lp-Space (M,k))) = A1 A1 in CosetSet (M,k) by A1; then consider a being PartFunc of X,REAL such that A11: ( A1 = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A12: a in A1 by A11, Th38; set z = X --> 0; A13: X --> 0 in 0. (Pre-Lp-Space (M,k)) by A1, Th38, Th23; reconsider a1 = a, z1 = X --> 0 as VECTOR of (RLSp_LpFunct (M,k)) by A11, Th23; a + (X --> 0) = a1 + z1 by Th29 .= a1 + (0. (RLSp_LpFunct (M,k))) by Th32 .= a by RLVECT_1:def_4 ; hence A1 + (0. (Pre-Lp-Space (M,k))) = A1 by A1, A11, A12, A13, Def8; ::_thesis: verum end; thus Pre-Lp-Space (M,k) is right_complementable ::_thesis: ( Pre-Lp-Space (M,k) is vector-distributive & Pre-Lp-Space (M,k) is scalar-distributive & Pre-Lp-Space (M,k) is scalar-associative & Pre-Lp-Space (M,k) is scalar-unital ) proof let A1 be Element of (Pre-Lp-Space (M,k)); :: according to ALGSTR_0:def_16 ::_thesis: A1 is right_complementable A1 in CosetSet (M,k) by A1; then consider a being PartFunc of X,REAL such that A14: ( A1 = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A15: a in A1 by A14, Th38; reconsider a1 = a as VECTOR of (RLSp_LpFunct (M,k)) by A14; A16: (- 1) (#) a in Lp_Functions (M,k) by A14, Th26; set A2 = a.e-eq-class_Lp (((- 1) (#) a),M,k); a.e-eq-class_Lp (((- 1) (#) a),M,k) in CosetSet (M,k) by A16; then reconsider A2 = a.e-eq-class_Lp (((- 1) (#) a),M,k) as Element of (Pre-Lp-Space (M,k)) by A1; take A2 ; :: according to ALGSTR_0:def_11 ::_thesis: A1 + A2 = 0. (Pre-Lp-Space (M,k)) A17: (- 1) (#) a in A2 by Th38, A14, Th26; consider v, g being PartFunc of X,REAL such that A18: ( v in Lp_Functions (M,k) & g in Lp_Functions (M,k) & v = a1 + ((- 1) * a1) & g = X --> 0 & v a.e.= g,M ) by Th31; (- 1) (#) a = (- 1) * a1 by Th30; then a + ((- 1) (#) a) a.e.= g,M by Th29, A18; then 0. (Pre-Lp-Space (M,k)) = a.e-eq-class_Lp ((a + ((- 1) (#) a)),M,k) by Th42, A18, A1; hence A1 + A2 = 0. (Pre-Lp-Space (M,k)) by A15, A17, Def8, A1; ::_thesis: verum end; now__::_thesis:_for_x0,_y0_being_real_number_ for_A1,_A2_being_Element_of_(Pre-Lp-Space_(M,k))_holds_ (_x0_*_(A1_+_A2)_=_(x0_*_A1)_+_(x0_*_A2)_&_(x0_+_y0)_*_A1_=_(x0_*_A1)_+_(y0_*_A1)_&_(x0_*_y0)_*_A1_=_x0_*_(y0_*_A1)_&_1_*_A1_=_A1_) let x0, y0 be real number ; ::_thesis: for A1, A2 being Element of (Pre-Lp-Space (M,k)) holds ( x0 * (A1 + A2) = (x0 * A1) + (x0 * A2) & (x0 + y0) * A1 = (x0 * A1) + (y0 * A1) & (x0 * y0) * A1 = x0 * (y0 * A1) & 1 * A1 = A1 ) let A1, A2 be Element of (Pre-Lp-Space (M,k)); ::_thesis: ( x0 * (A1 + A2) = (x0 * A1) + (x0 * A2) & (x0 + y0) * A1 = (x0 * A1) + (y0 * A1) & (x0 * y0) * A1 = x0 * (y0 * A1) & 1 * A1 = A1 ) reconsider x = x0, y = y0 as Real by XREAL_0:def_1; A1 in CosetSet (M,k) by A1; then consider a being PartFunc of X,REAL such that A19: ( A1 = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A2 in CosetSet (M,k) by A1; then consider b being PartFunc of X,REAL such that A20: ( A2 = a.e-eq-class_Lp (b,M,k) & b in Lp_Functions (M,k) ) ; A21: ( a in A1 & b in A2 ) by A19, A20, Th38; then (addCoset (M,k)) . (A1,A2) = a.e-eq-class_Lp ((a + b),M,k) by A1, Def8; then A22: a + b in A1 + A2 by Th38, Th25, A19, A20, A1; reconsider a1 = a, b1 = b as VECTOR of (RLSp_LpFunct (M,k)) by A19, A20; A23: ( y (#) a = y * a1 & x (#) a = x * a1 & x (#) b = x * b1 & (x + y) (#) a = (x + y) * a1 & 1 (#) a = 1 * a1 ) by Th30; a + b = a1 + b1 by Th29; then x (#) (a + b) = x * (a1 + b1) by Th30; then x (#) (a + b) = (x * a1) + (x * b1) by RLVECT_1:def_5; then A24: x (#) (a + b) = (x (#) a) + (x (#) b) by A23, Th29; (x + y) (#) a = (x * a1) + (y * a1) by A23, RLVECT_1:def_6; then A25: (x + y) (#) a = (x (#) a) + (y (#) a) by A23, Th29; x (#) (y (#) a) = x * (y * a1) by A23, Th30 .= (x * y) * a1 by RLVECT_1:def_7 ; then A26: x (#) (y (#) a) = (x * y) (#) a by Th30; ( (lmultCoset (M,k)) . (x,A1) = a.e-eq-class_Lp ((x (#) a),M,k) & (lmultCoset (M,k)) . (x,A2) = a.e-eq-class_Lp ((x (#) b),M,k) & (lmultCoset (M,k)) . (y,A1) = a.e-eq-class_Lp ((y (#) a),M,k) ) by A1, A21, Def10; then A27: ( x (#) a in x * A1 & x (#) b in x * A2 & y (#) a in y * A1 ) by A1, Th38, Th26, A19, A20; x * (A1 + A2) = a.e-eq-class_Lp (((x (#) a) + (x (#) b)),M,k) by A1, A24, A22, Def10; hence x0 * (A1 + A2) = (x0 * A1) + (x0 * A2) by A1, A27, Def8; ::_thesis: ( (x0 + y0) * A1 = (x0 * A1) + (y0 * A1) & (x0 * y0) * A1 = x0 * (y0 * A1) & 1 * A1 = A1 ) (x + y) * A1 = a.e-eq-class_Lp (((x (#) a) + (y (#) a)),M,k) by A1, A25, A21, Def10; hence (x0 + y0) * A1 = (x0 * A1) + (y0 * A1) by A27, Def8, A1; ::_thesis: ( (x0 * y0) * A1 = x0 * (y0 * A1) & 1 * A1 = A1 ) (x0 * y0) * A1 = a.e-eq-class_Lp ((x (#) (y (#) a)),M,k) by A1, A26, A21, Def10; hence (x0 * y0) * A1 = x0 * (y0 * A1) by A27, Def10, A1; ::_thesis: 1 * A1 = A1 1 (#) a = a by A23, RLVECT_1:def_8; hence 1 * A1 = A1 by A19, A21, Def10, A1; ::_thesis: verum end; hence ( Pre-Lp-Space (M,k) is vector-distributive & Pre-Lp-Space (M,k) is scalar-distributive & Pre-Lp-Space (M,k) is scalar-associative & Pre-Lp-Space (M,k) is scalar-unital ) by RLVECT_1:def_5, RLVECT_1:def_6, RLVECT_1:def_7, RLVECT_1:def_8; ::_thesis: verum end; end; begin theorem Th48: :: LPSPACE2:48 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M holds Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M holds Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M holds Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M holds Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M holds Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M implies Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) set t = (abs f) to_power k; set s = (abs g) to_power k; assume A1: ( f in Lp_Functions (M,k) & g in Lp_Functions (M,k) & f a.e.= g,M ) ; ::_thesis: Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) then ex f1 being PartFunc of X,REAL st ( f = f1 & ex E being Element of S st ( M . (E `) = 0 & dom f1 = E & f1 is_measurable_on E & (abs f1) to_power k is_integrable_on M ) ) ; then consider Df being Element of S such that A2: ( M . (Df `) = 0 & dom f = Df & f is_measurable_on Df & (abs f) to_power k is_integrable_on M ) ; ex g1 being PartFunc of X,REAL st ( g = g1 & ex E being Element of S st ( M . (E `) = 0 & dom g1 = E & g1 is_measurable_on E & (abs g1) to_power k is_integrable_on M ) ) by A1; then consider Dg being Element of S such that A3: ( M . (Dg `) = 0 & dom g = Dg & g is_measurable_on Dg & (abs g) to_power k is_integrable_on M ) ; A4: ( dom (abs f) = dom f & dom (abs g) = dom g ) by VALUED_1:def_11; consider E1 being Element of S such that A5: ( M . E1 = 0 & f | (E1 `) = g | (E1 `) ) by A1, LPSPACE1:def_10; reconsider NDf = Df ` , NDg = Dg ` as Element of S by MEASURE1:34; set Ef = Df \ (NDg \/ E1); set Eg = Dg \ (NDf \/ E1); set E2 = (NDf \/ NDg) \/ E1; ( NDf is measure_zero of M & NDg is measure_zero of M & E1 is measure_zero of M ) by A2, A3, A5, MEASURE1:def_7; then ( NDf \/ E1 is measure_zero of M & NDg \/ E1 is measure_zero of M ) by MEASURE1:37; then A6: ( M . (NDf \/ E1) = 0 & M . (NDg \/ E1) = 0 ) by MEASURE1:def_7; ( X \ NDf = X /\ Df & X \ NDg = X /\ Dg ) by XBOOLE_1:48; then A7: ( X \ NDf = Df & X \ NDg = Dg ) by XBOOLE_1:28; ( Df \ (NDg \/ E1) = (Df \ NDg) \ E1 & Dg \ (NDf \/ E1) = (Dg \ NDf) \ E1 ) by XBOOLE_1:41; then A8: ( Df \ (NDg \/ E1) = (X \ (NDf \/ NDg)) \ E1 & Dg \ (NDf \/ E1) = (X \ (NDf \/ NDg)) \ E1 ) by A7, XBOOLE_1:41; then A9: ( Df \ (NDg \/ E1) = X \ ((NDf \/ NDg) \/ E1) & Dg \ (NDf \/ E1) = X \ ((NDf \/ NDg) \/ E1) ) by XBOOLE_1:41; ( abs f is_measurable_on Df & abs g is_measurable_on Dg ) by A2, A3, MESFUNC6:48; then A10: ( (abs f) to_power k is_measurable_on Df & (abs g) to_power k is_measurable_on Dg ) by A2, A3, A4, MESFUN6C:29; A11: ( dom ((abs f) to_power k) = Df & dom ((abs g) to_power k) = Dg ) by A2, A3, A4, MESFUN6C:def_4; then A12: ( Integral (M,(((abs f) to_power k) | (Df \ (NDg \/ E1)))) = Integral (M,((abs f) to_power k)) & Integral (M,(((abs g) to_power k) | (Dg \ (NDf \/ E1)))) = Integral (M,((abs g) to_power k)) ) by A6, A10, MESFUNC6:89; ( dom (((abs f) to_power k) | (Df \ (NDg \/ E1))) = (dom ((abs f) to_power k)) /\ (Df \ (NDg \/ E1)) & dom (((abs g) to_power k) | (Df \ (NDg \/ E1))) = (dom ((abs g) to_power k)) /\ (Df \ (NDg \/ E1)) ) by RELAT_1:61; then A13: ( dom (((abs f) to_power k) | (Df \ (NDg \/ E1))) = (Df /\ Df) \ (NDg \/ E1) & dom (((abs g) to_power k) | (Df \ (NDg \/ E1))) = (Dg /\ Dg) \ (NDf \/ E1) ) by A11, A8, XBOOLE_1:49; now__::_thesis:_for_x_being_Element_of_X_st_x_in_dom_(((abs_f)_to_power_k)_|_(Df_\_(NDg_\/_E1)))_holds_ (((abs_f)_to_power_k)_|_(Df_\_(NDg_\/_E1)))_._x_=_(((abs_g)_to_power_k)_|_(Df_\_(NDg_\/_E1)))_._x let x be Element of X; ::_thesis: ( x in dom (((abs f) to_power k) | (Df \ (NDg \/ E1))) implies (((abs f) to_power k) | (Df \ (NDg \/ E1))) . x = (((abs g) to_power k) | (Df \ (NDg \/ E1))) . x ) assume A14: x in dom (((abs f) to_power k) | (Df \ (NDg \/ E1))) ; ::_thesis: (((abs f) to_power k) | (Df \ (NDg \/ E1))) . x = (((abs g) to_power k) | (Df \ (NDg \/ E1))) . x A15: ( dom (((abs f) to_power k) | (Df \ (NDg \/ E1))) c= dom ((abs f) to_power k) & dom (((abs g) to_power k) | (Df \ (NDg \/ E1))) c= dom ((abs g) to_power k) ) by RELAT_1:60; ((NDf \/ NDg) \/ E1) ` c= E1 ` by XBOOLE_1:7, XBOOLE_1:34; then A16: ( f . x = (f | (E1 `)) . x & g . x = (g | (E1 `)) . x ) by A14, A13, A9, FUNCT_1:49; ( (((abs f) to_power k) | (Df \ (NDg \/ E1))) . x = ((abs f) to_power k) . x & (((abs g) to_power k) | (Df \ (NDg \/ E1))) . x = ((abs g) to_power k) . x ) by A14, A13, FUNCT_1:49; then ( (((abs f) to_power k) | (Df \ (NDg \/ E1))) . x = ((abs f) . x) to_power k & (((abs g) to_power k) | (Df \ (NDg \/ E1))) . x = ((abs g) . x) to_power k ) by A8, A13, A14, A15, MESFUN6C:def_4; then ( (((abs f) to_power k) | (Df \ (NDg \/ E1))) . x = (abs (f . x)) to_power k & (((abs g) to_power k) | (Df \ (NDg \/ E1))) . x = (abs (g . x)) to_power k ) by VALUED_1:18; hence (((abs f) to_power k) | (Df \ (NDg \/ E1))) . x = (((abs g) to_power k) | (Df \ (NDg \/ E1))) . x by A5, A16; ::_thesis: verum end; hence Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) by A12, A13, A8, PARTFUN1:5; ::_thesis: verum end; theorem Th49: :: LPSPACE2:49 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) holds ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) implies ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) ) assume f in Lp_Functions (M,k) ; ::_thesis: ( Integral (M,((abs f) to_power k)) in REAL & 0 <= Integral (M,((abs f) to_power k)) ) then A1: ex f1 being PartFunc of X,REAL st ( f = f1 & ex ND being Element of S st ( M . (ND `) = 0 & dom f1 = ND & f1 is_measurable_on ND & (abs f1) to_power k is_integrable_on M ) ) ; then ( -infty < Integral (M,((abs f) to_power k)) & Integral (M,((abs f) to_power k)) < +infty ) by MESFUNC6:90; hence Integral (M,((abs f) to_power k)) in REAL by XXREAL_0:14; ::_thesis: 0 <= Integral (M,((abs f) to_power k)) R_EAL ((abs f) to_power k) is_integrable_on M by A1, MESFUNC6:def_4; then consider A being Element of S such that A2: ( A = dom (R_EAL ((abs f) to_power k)) & R_EAL ((abs f) to_power k) is_measurable_on A ) by MESFUNC5:def_17; ( A = dom ((abs f) to_power k) & (abs f) to_power k is_measurable_on A ) by A2, MESFUNC6:def_1; hence 0 <= Integral (M,((abs f) to_power k)) by MESFUNC6:84; ::_thesis: verum end; theorem Th50: :: LPSPACE2:50 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) holds ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) holds ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real st ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) holds ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real st ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) holds ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real st ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) holds ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) let k be positive Real; ::_thesis: ( ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) implies ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) ) assume ex x being VECTOR of (Pre-Lp-Space (M,k)) st ( f in x & g in x ) ; ::_thesis: ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) then consider x being VECTOR of (Pre-Lp-Space (M,k)) such that A1: ( f in x & g in x ) ; x in the carrier of (Pre-Lp-Space (M,k)) ; then x in CosetSet (M,k) by Def11; then consider h being PartFunc of X,REAL such that A2: ( x = a.e-eq-class_Lp (h,M,k) & h in Lp_Functions (M,k) ) ; ( ex i being PartFunc of X,REAL st ( f = i & i in Lp_Functions (M,k) & h a.e.= i,M ) & ex j being PartFunc of X,REAL st ( g = j & j in Lp_Functions (M,k) & h a.e.= j,M ) ) by A1, A2; then ( f a.e.= h,M & h a.e.= g,M ) by LPSPACE1:29; hence ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) by A1, A2, LPSPACE1:30; ::_thesis: verum end; theorem Th51: :: LPSPACE2:51 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x holds ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x holds ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x holds ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x holds ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x holds ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) let k be positive Real; ::_thesis: for x being Point of (Pre-Lp-Space (M,k)) st f in x holds ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) let x be Point of (Pre-Lp-Space (M,k)); ::_thesis: ( f in x implies ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) ) assume A1: f in x ; ::_thesis: ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) x in the carrier of (Pre-Lp-Space (M,k)) ; then x in CosetSet (M,k) by Def11; then consider h being PartFunc of X,REAL such that A2: ( x = a.e-eq-class_Lp (h,M,k) & h in Lp_Functions (M,k) ) ; ex g being PartFunc of X,REAL st ( f = g & g in Lp_Functions (M,k) & h a.e.= g,M ) by A1, A2; then ex f0 being PartFunc of X,REAL st ( f = f0 & ex ND being Element of S st ( M . (ND `) = 0 & dom f0 = ND & f0 is_measurable_on ND & (abs f0) to_power k is_integrable_on M ) ) ; hence ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) ; ::_thesis: verum end; theorem Th52: :: LPSPACE2:52 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x & g in x holds ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x & g in x holds ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x & g in x holds ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x & g in x holds ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) let f, g be PartFunc of X,REAL; ::_thesis: for k being positive Real for x being Point of (Pre-Lp-Space (M,k)) st f in x & g in x holds ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) let k be positive Real; ::_thesis: for x being Point of (Pre-Lp-Space (M,k)) st f in x & g in x holds ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) let x be Point of (Pre-Lp-Space (M,k)); ::_thesis: ( f in x & g in x implies ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) ) assume ( f in x & g in x ) ; ::_thesis: ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) then ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) by Th50; hence ( f a.e.= g,M & Integral (M,((abs f) to_power k)) = Integral (M,((abs g) to_power k)) ) by Th48; ::_thesis: verum end; definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func Lp-Norm (M,k) -> Function of the carrier of (Pre-Lp-Space (M,k)),REAL means :Def12: :: LPSPACE2:def 12 for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & it . x = r to_power (1 / k) ) ); existence ex b1 being Function of the carrier of (Pre-Lp-Space (M,k)),REAL st for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & b1 . x = r to_power (1 / k) ) ) proof defpred S1[ set , set ] means ex f being PartFunc of X,REAL st ( f in $1 & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & $2 = r to_power (1 / k) ) ); A1: for x being Point of (Pre-Lp-Space (M,k)) ex y being Element of REAL st S1[x,y] proof let x be Point of (Pre-Lp-Space (M,k)); ::_thesis: ex y being Element of REAL st S1[x,y] x in the carrier of (Pre-Lp-Space (M,k)) ; then x in CosetSet (M,k) by Def11; then consider f being PartFunc of X,REAL such that A2: ( x = a.e-eq-class_Lp (f,M,k) & f in Lp_Functions (M,k) ) ; reconsider r1 = Integral (M,((abs f) to_power k)) as Element of REAL by A2, Th49; r1 to_power (1 / k) in REAL ; hence ex y being Element of REAL st S1[x,y] by A2, Th38; ::_thesis: verum end; consider F being Function of the carrier of (Pre-Lp-Space (M,k)),REAL such that A3: for x being Point of (Pre-Lp-Space (M,k)) holds S1[x,F . x] from FUNCT_2:sch_3(A1); take F ; ::_thesis: for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & F . x = r to_power (1 / k) ) ) thus for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & F . x = r to_power (1 / k) ) ) by A3; ::_thesis: verum end; uniqueness for b1, b2 being Function of the carrier of (Pre-Lp-Space (M,k)),REAL st ( for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & b1 . x = r to_power (1 / k) ) ) ) & ( for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & b2 . x = r to_power (1 / k) ) ) ) holds b1 = b2 proof let N1, N2 be Function of the carrier of (Pre-Lp-Space (M,k)),REAL; ::_thesis: ( ( for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & N1 . x = r to_power (1 / k) ) ) ) & ( for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & N2 . x = r to_power (1 / k) ) ) ) implies N1 = N2 ) assume A4: ( ( for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r1 being Real st ( r1 = Integral (M,((abs f) to_power k)) & N1 . x = r1 to_power (1 / k) ) ) ) & ( for x being Point of (Pre-Lp-Space (M,k)) ex g being PartFunc of X,REAL st ( g in x & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power k)) & N2 . x = r2 to_power (1 / k) ) ) ) ) ; ::_thesis: N1 = N2 now__::_thesis:_for_x_being_Point_of_(Pre-Lp-Space_(M,k))_holds_N1_._x_=_N2_._x let x be Point of (Pre-Lp-Space (M,k)); ::_thesis: N1 . x = N2 . x ( ex f being PartFunc of X,REAL st ( f in x & ex r1 being Real st ( r1 = Integral (M,((abs f) to_power k)) & N1 . x = r1 to_power (1 / k) ) ) & ex g being PartFunc of X,REAL st ( g in x & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power k)) & N2 . x = r2 to_power (1 / k) ) ) ) by A4; hence N1 . x = N2 . x by Th52; ::_thesis: verum end; hence N1 = N2 by FUNCT_2:63; ::_thesis: verum end; end; :: deftheorem Def12 defines Lp-Norm LPSPACE2:def_12_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for b5 being Function of the carrier of (Pre-Lp-Space (M,k)),REAL holds ( b5 = Lp-Norm (M,k) iff for x being Point of (Pre-Lp-Space (M,k)) ex f being PartFunc of X,REAL st ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & b5 . x = r to_power (1 / k) ) ) ); definition let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be positive Real; func Lp-Space (M,k) -> non empty NORMSTR equals :: LPSPACE2:def 13 NORMSTR(# the carrier of (Pre-Lp-Space (M,k)), the ZeroF of (Pre-Lp-Space (M,k)), the addF of (Pre-Lp-Space (M,k)), the Mult of (Pre-Lp-Space (M,k)),(Lp-Norm (M,k)) #); coherence NORMSTR(# the carrier of (Pre-Lp-Space (M,k)), the ZeroF of (Pre-Lp-Space (M,k)), the addF of (Pre-Lp-Space (M,k)), the Mult of (Pre-Lp-Space (M,k)),(Lp-Norm (M,k)) #) is non empty NORMSTR ; end; :: deftheorem defines Lp-Space LPSPACE2:def_13_:_ for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds Lp-Space (M,k) = NORMSTR(# the carrier of (Pre-Lp-Space (M,k)), the ZeroF of (Pre-Lp-Space (M,k)), the addF of (Pre-Lp-Space (M,k)), the Mult of (Pre-Lp-Space (M,k)),(Lp-Norm (M,k)) #); theorem Th53: :: LPSPACE2:53 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for x being Point of (Lp-Space (M,k)) holds ( ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) & ( for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for x being Point of (Lp-Space (M,k)) holds ( ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) & ( for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real for x being Point of (Lp-Space (M,k)) holds ( ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) & ( for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) let M be sigma_Measure of S; ::_thesis: for k being positive Real for x being Point of (Lp-Space (M,k)) holds ( ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) & ( for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) let k be positive Real; ::_thesis: for x being Point of (Lp-Space (M,k)) holds ( ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) & ( for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) let x be Point of (Lp-Space (M,k)); ::_thesis: ( ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) & ( for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) x in the carrier of (Pre-Lp-Space (M,k)) ; then x in CosetSet (M,k) by Def11; then ex g being PartFunc of X,REAL st ( x = a.e-eq-class_Lp (g,M,k) & g in Lp_Functions (M,k) ) ; hence ex f being PartFunc of X,REAL st ( f in Lp_Functions (M,k) & x = a.e-eq-class_Lp (f,M,k) ) ; ::_thesis: for f being PartFunc of X,REAL st f in x holds ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) consider f being PartFunc of X,REAL such that A1: ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & (Lp-Norm (M,k)) . x = r to_power (1 / k) ) ) by Def12; hereby ::_thesis: verum let g be PartFunc of X,REAL; ::_thesis: ( g in x implies ex r being Real st ( 0 <= r & r = Integral (M,((abs g) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) assume A2: g in x ; ::_thesis: ex r being Real st ( 0 <= r & r = Integral (M,((abs g) to_power k)) & ||.x.|| = r to_power (1 / k) ) then A3: g in Lp_Functions (M,k) by Th50; Integral (M,((abs g) to_power k)) = Integral (M,((abs f) to_power k)) by A1, Th52, A2; hence ex r being Real st ( 0 <= r & r = Integral (M,((abs g) to_power k)) & ||.x.|| = r to_power (1 / k) ) by A1, A3, Th49; ::_thesis: verum end; end; theorem Th54: :: LPSPACE2:54 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for a being Real for k being positive Real for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for a being Real for k being positive Real for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) let f, g be PartFunc of X,REAL; ::_thesis: for a being Real for k being positive Real for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) let a be Real; ::_thesis: for k being positive Real for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) let k be positive Real; ::_thesis: for x, y being Point of (Lp-Space (M,k)) holds ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) let x, y be Point of (Lp-Space (M,k)); ::_thesis: ( ( f in x & g in y implies f + g in x + y ) & ( f in x implies a (#) f in a * x ) ) set C = CosetSet (M,k); hereby ::_thesis: ( f in x implies a (#) f in a * x ) assume A1: ( f in x & g in y ) ; ::_thesis: f + g in x + y x in the carrier of (Pre-Lp-Space (M,k)) ; then A2: x in CosetSet (M,k) by Def11; then consider a being PartFunc of X,REAL such that A3: ( x = a.e-eq-class_Lp (a,M,k) & a in Lp_Functions (M,k) ) ; A4: a in x by A3, Th38; y in the carrier of (Pre-Lp-Space (M,k)) ; then A5: y in CosetSet (M,k) by Def11; then consider b being PartFunc of X,REAL such that A6: ( y = a.e-eq-class_Lp (b,M,k) & b in Lp_Functions (M,k) ) ; b in y by A6, Th38; then (addCoset (M,k)) . (x,y) = a.e-eq-class_Lp ((a + b),M,k) by A2, A5, A4, Def8; then A7: x + y = a.e-eq-class_Lp ((a + b),M,k) by Def11; ex r being PartFunc of X,REAL st ( f = r & r in Lp_Functions (M,k) & a a.e.= r,M ) by A1, A3; then A8: a.e-eq-class_Lp (a,M,k) = a.e-eq-class_Lp (f,M,k) by Th42; ex r being PartFunc of X,REAL st ( g = r & r in Lp_Functions (M,k) & b a.e.= r,M ) by A1, A6; then a.e-eq-class_Lp (b,M,k) = a.e-eq-class_Lp (g,M,k) by Th42; then a.e-eq-class_Lp ((a + b),M,k) = a.e-eq-class_Lp ((f + g),M,k) by A1, A3, A6, A8, Th45; hence f + g in x + y by Th38, A7, Th25, A3, A1, A6; ::_thesis: verum end; hereby ::_thesis: verum assume A9: f in x ; ::_thesis: a (#) f in a * x x in the carrier of (Pre-Lp-Space (M,k)) ; then A10: x in CosetSet (M,k) by Def11; then consider f1 being PartFunc of X,REAL such that A11: ( x = a.e-eq-class_Lp (f1,M,k) & f1 in Lp_Functions (M,k) ) ; f1 in x by A11, Th38; then (lmultCoset (M,k)) . (a,x) = a.e-eq-class_Lp ((a (#) f1),M,k) by A10, Def10; then A12: a * x = a.e-eq-class_Lp ((a (#) f1),M,k) by Def11; ex r being PartFunc of X,REAL st ( f = r & r in Lp_Functions (M,k) & f1 a.e.= r,M ) by A9, A11; then a.e-eq-class_Lp (f1,M,k) = a.e-eq-class_Lp (f,M,k) by Th42; then a.e-eq-class_Lp ((a (#) f1),M,k) = a.e-eq-class_Lp ((a (#) f),M,k) by A11, A9, Th47; hence a (#) f in a * x by A12, Th26, A9, A11, Th38; ::_thesis: verum end; end; theorem Th55: :: LPSPACE2:55 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for x being Point of (Lp-Space (M,k)) st f in x holds ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for x being Point of (Lp-Space (M,k)) st f in x holds ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real for x being Point of (Lp-Space (M,k)) st f in x holds ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real for x being Point of (Lp-Space (M,k)) st f in x holds ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) let f be PartFunc of X,REAL; ::_thesis: for k being positive Real for x being Point of (Lp-Space (M,k)) st f in x holds ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) let k be positive Real; ::_thesis: for x being Point of (Lp-Space (M,k)) st f in x holds ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) let x be Point of (Lp-Space (M,k)); ::_thesis: ( f in x implies ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) ) assume A1: f in x ; ::_thesis: ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) x in the carrier of (Pre-Lp-Space (M,k)) ; then x in CosetSet (M,k) by Def11; then consider g being PartFunc of X,REAL such that A2: ( x = a.e-eq-class_Lp (g,M,k) & g in Lp_Functions (M,k) ) ; g in x by A2, Th38; then ( f a.e.= g,M & f in Lp_Functions (M,k) & g in Lp_Functions (M,k) ) by A1, Th50; hence ( x = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) by Th53, A1, A2, Th42; ::_thesis: verum end; theorem Th56: :: LPSPACE2:56 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds X --> 0 in L1_Functions M proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds X --> 0 in L1_Functions M let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds X --> 0 in L1_Functions M let M be sigma_Measure of S; ::_thesis: X --> 0 in L1_Functions M reconsider ND = {} as Element of S by MEASURE1:34; A1: M . ND = 0 by VALUED_0:def_19; X --> 0 is Function of X,REAL by FUNCOP_1:46; then A2: dom (X --> 0) = ND ` by FUNCT_2:def_1; for x being Element of X st x in dom (X --> 0) holds (X --> 0) . x = 0 by FUNCOP_1:7; then X --> 0 is_integrable_on M by A2, Th15; hence X --> 0 in L1_Functions M by A1, A2; ::_thesis: verum end; theorem Th57: :: LPSPACE2:57 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & Integral (M,((abs f) to_power k)) = 0 holds f a.e.= X --> 0,M proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & Integral (M,((abs f) to_power k)) = 0 holds f a.e.= X --> 0,M let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & Integral (M,((abs f) to_power k)) = 0 holds f a.e.= X --> 0,M let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) & Integral (M,((abs f) to_power k)) = 0 holds f a.e.= X --> 0,M let f be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) & Integral (M,((abs f) to_power k)) = 0 holds f a.e.= X --> 0,M let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) & Integral (M,((abs f) to_power k)) = 0 implies f a.e.= X --> 0,M ) assume that A1: f in Lp_Functions (M,k) and A2: Integral (M,((abs f) to_power k)) = 0 ; ::_thesis: f a.e.= X --> 0,M ex h being PartFunc of X,REAL st ( f = h & ex ND being Element of S st ( M . (ND `) = 0 & dom h = ND & h is_measurable_on ND & (abs h) to_power k is_integrable_on M ) ) by A1; then consider NDf being Element of S such that A3: ( M . (NDf `) = 0 & dom f = NDf & f is_measurable_on NDf & (abs f) to_power k is_integrable_on M ) ; reconsider t = (abs f) to_power k as PartFunc of X,REAL ; reconsider ND = NDf ` as Element of S by MEASURE1:34; A4: dom t = dom (abs f) by MESFUN6C:def_4; then A5: dom t = NDf by A3, VALUED_1:def_11; dom t = ND ` by A4, A3, VALUED_1:def_11; then A6: t in L1_Functions M by A3; abs t = t by Th14; then t a.e.= X --> 0,M by A2, A6, LPSPACE1:53; then consider ND1 being Element of S such that A7: ( M . ND1 = 0 & ((abs f) to_power k) | (ND1 `) = (X --> 0) | (ND1 `) ) by LPSPACE1:def_10; set ND2 = ND \/ ND1; ( ND is measure_zero of M & ND1 is measure_zero of M ) by A3, A7, MEASURE1:def_7; then ND \/ ND1 is measure_zero of M by MEASURE1:37; then A8: M . (ND \/ ND1) = 0 by MEASURE1:def_7; A9: ( (ND \/ ND1) ` c= ND ` & (ND \/ ND1) ` c= ND1 ` ) by XBOOLE_1:7, XBOOLE_1:34; dom (X --> 0) = X by FUNCOP_1:13; then A10: dom ((X --> 0) | ((ND \/ ND1) `)) = (ND \/ ND1) ` by RELAT_1:62; A11: dom (f | ((ND \/ ND1) `)) = (ND \/ ND1) ` by A3, A9, RELAT_1:62; for x being set st x in dom (f | ((ND \/ ND1) `)) holds (f | ((ND \/ ND1) `)) . x = ((X --> 0) | ((ND \/ ND1) `)) . x proof let x be set ; ::_thesis: ( x in dom (f | ((ND \/ ND1) `)) implies (f | ((ND \/ ND1) `)) . x = ((X --> 0) | ((ND \/ ND1) `)) . x ) assume A12: x in dom (f | ((ND \/ ND1) `)) ; ::_thesis: (f | ((ND \/ ND1) `)) . x = ((X --> 0) | ((ND \/ ND1) `)) . x A13: now__::_thesis:_not_f_._x_<>_0 assume f . x <> 0 ; ::_thesis: contradiction then abs (f . x) > 0 by COMPLEX1:47; then (abs (f . x)) to_power k <> 0 by POWER:34; then ((abs f) . x) to_power k <> 0 by VALUED_1:18; then A14: ((abs f) to_power k) . x <> 0 by A5, A9, A12, A11, MESFUN6C:def_4; ((X --> 0) | (ND1 `)) . x = (X --> 0) . x by A9, A12, A11, FUNCT_1:49; then ((X --> 0) | (ND1 `)) . x = 0 by A12, FUNCOP_1:7; hence contradiction by A14, A7, A9, A12, A11, FUNCT_1:49; ::_thesis: verum end; ((X --> 0) | ((ND \/ ND1) `)) . x = (X --> 0) . x by A11, A12, FUNCT_1:49; then ((X --> 0) | ((ND \/ ND1) `)) . x = 0 by A12, FUNCOP_1:7; hence (f | ((ND \/ ND1) `)) . x = ((X --> 0) | ((ND \/ ND1) `)) . x by A11, A12, A13, FUNCT_1:49; ::_thesis: verum end; then f | ((ND \/ ND1) `) = (X --> 0) | ((ND \/ ND1) `) by A10, A11, FUNCT_1:def_11; hence f a.e.= X --> 0,M by A8, LPSPACE1:def_10; ::_thesis: verum end; theorem Th58: :: LPSPACE2:58 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds Integral (M,((abs (X --> 0)) to_power k)) = 0 proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real holds Integral (M,((abs (X --> 0)) to_power k)) = 0 let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real holds Integral (M,((abs (X --> 0)) to_power k)) = 0 let M be sigma_Measure of S; ::_thesis: for k being positive Real holds Integral (M,((abs (X --> 0)) to_power k)) = 0 let k be positive Real; ::_thesis: Integral (M,((abs (X --> 0)) to_power k)) = 0 A1: for x being set st x in dom (X --> 0) holds 0 <= (X --> 0) . x ; then Integral (M,((abs (X --> 0)) to_power k)) = Integral (M,((X --> 0) to_power k)) by Th14, MESFUNC6:52 .= Integral (M,(X --> 0)) by Th12 .= Integral (M,(abs (X --> 0))) by A1, Th14, MESFUNC6:52 ; hence Integral (M,((abs (X --> 0)) to_power k)) = 0 by LPSPACE1:54; ::_thesis: verum end; theorem Th59: :: LPSPACE2:59 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) let f, g be PartFunc of X,REAL; ::_thesis: for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) let m, n be positive Real; ::_thesis: ( (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) implies ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) ) assume that A1: (1 / m) + (1 / n) = 1 and A2: ( f in Lp_Functions (M,m) & g in Lp_Functions (M,n) ) ; ::_thesis: ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) A3: ( m > 1 & n > 1 ) by A1, Th1; consider f1 being PartFunc of X,REAL such that A4: ( f = f1 & ex NDf being Element of S st ( M . (NDf `) = 0 & dom f1 = NDf & f1 is_measurable_on NDf & (abs f1) to_power m is_integrable_on M ) ) by A2; consider EDf being Element of S such that A5: ( M . (EDf `) = 0 & dom f1 = EDf & f1 is_measurable_on EDf ) by A4; consider g1 being PartFunc of X,REAL such that A6: ( g = g1 & ex NDg being Element of S st ( M . (NDg `) = 0 & dom g1 = NDg & g1 is_measurable_on NDg & (abs g1) to_power n is_integrable_on M ) ) by A2; consider EDg being Element of S such that A7: ( M . (EDg `) = 0 & dom g1 = EDg & g1 is_measurable_on EDg ) by A6; set u = (abs f1) to_power m; set v = (abs g1) to_power n; set w = f1 (#) g1; set z = ((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n)); A8: ( dom f1 = dom (abs f1) & dom g1 = dom (abs g1) ) by VALUED_1:def_11; then A9: ( dom ((abs f1) to_power m) = dom f1 & dom ((abs g1) to_power n) = dom g1 ) by MESFUN6C:def_4; then A10: dom (f1 (#) g1) = (dom ((abs f1) to_power m)) /\ (dom ((abs g1) to_power n)) by VALUED_1:def_4; set Nf = EDf ` ; set Ng = EDg ` ; set E = EDf /\ EDg; reconsider Nf = EDf ` , Ng = EDg ` as Element of S by MEASURE1:34; ( dom ((abs f1) to_power m) = Nf ` & dom ((abs g1) to_power n) = Ng ` ) by A5, A7, A8, MESFUN6C:def_4; then ( (abs f1) to_power m in L1_Functions M & (abs g1) to_power n in L1_Functions M ) by A4, A5, A6, A7; then ( (1 / m) (#) ((abs f1) to_power m) in L1_Functions M & (1 / n) (#) ((abs g1) to_power n) in L1_Functions M ) by LPSPACE1:24; then ((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n)) in L1_Functions M by LPSPACE1:23; then A11: ex h being PartFunc of X,REAL st ( ((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n)) = h & ex ND being Element of S st ( M . ND = 0 & dom h = ND ` & h is_integrable_on M ) ) ; ( dom ((1 / m) (#) ((abs f1) to_power m)) = dom ((abs f1) to_power m) & dom ((1 / n) (#) ((abs g1) to_power n)) = dom ((abs g1) to_power n) ) by VALUED_1:def_5; then A12: dom (((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n))) = (dom ((abs f1) to_power m)) /\ (dom ((abs g1) to_power n)) by VALUED_1:def_1; A13: (EDf /\ EDg) ` = (EDf `) \/ (EDg `) by XBOOLE_1:54; ( Nf is measure_zero of M & Ng is measure_zero of M ) by A5, A7, MEASURE1:def_7; then Nf \/ Ng is measure_zero of M by MEASURE1:37; then A14: M . ((EDf /\ EDg) `) = 0 by A13, MEASURE1:def_7; ( f1 is_measurable_on EDf /\ EDg & g1 is_measurable_on EDf /\ EDg ) by A5, A7, MESFUNC6:16, XBOOLE_1:17; then A15: f1 (#) g1 is_measurable_on EDf /\ EDg by A5, A7, MESFUN7C:31; for x being Element of X st x in dom (f1 (#) g1) holds abs ((f1 (#) g1) . x) <= (((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n))) . x proof let x be Element of X; ::_thesis: ( x in dom (f1 (#) g1) implies abs ((f1 (#) g1) . x) <= (((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n))) . x ) assume A16: x in dom (f1 (#) g1) ; ::_thesis: abs ((f1 (#) g1) . x) <= (((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n))) . x abs (f1 (#) g1) = (abs f1) (#) (abs g1) by RFUNCT_1:24; then (abs (f1 (#) g1)) . x = ((abs f1) . x) * ((abs g1) . x) by VALUED_1:5; then A17: abs ((f1 (#) g1) . x) = ((abs f1) . x) * ((abs g1) . x) by VALUED_1:18; A18: ( (abs f1) . x >= 0 & (abs g1) . x >= 0 ) by MESFUNC6:51; ( x in dom ((abs f1) to_power m) & x in dom ((abs g1) to_power n) ) by A16, A10, XBOOLE_0:def_4; then ( (((abs f1) . x) to_power m) / m = (1 / m) * (((abs f1) to_power m) . x) & (((abs g1) . x) to_power n) / n = (1 / n) * (((abs g1) to_power n) . x) ) by MESFUN6C:def_4; then ( (((abs f1) . x) to_power m) / m = ((1 / m) (#) ((abs f1) to_power m)) . x & (((abs g1) . x) to_power n) / n = ((1 / n) (#) ((abs g1) to_power n)) . x ) by VALUED_1:6; then abs ((f1 (#) g1) . x) <= (((1 / m) (#) ((abs f1) to_power m)) . x) + (((1 / n) (#) ((abs g1) to_power n)) . x) by A1, A3, A17, A18, HOLDER_1:5; hence abs ((f1 (#) g1) . x) <= (((1 / m) (#) ((abs f1) to_power m)) + ((1 / n) (#) ((abs g1) to_power n))) . x by A16, A10, A12, VALUED_1:def_1; ::_thesis: verum end; then A19: f1 (#) g1 is_integrable_on M by A5, A7, A9, A10, A11, A15, A12, MESFUNC6:96; set ND = (EDf /\ EDg) ` ; reconsider ND = (EDf /\ EDg) ` as Element of S by MEASURE1:34; dom (f1 (#) g1) = ND ` by A5, A7, VALUED_1:def_4; hence ( f (#) g in L1_Functions M & f (#) g is_integrable_on M ) by A4, A6, A14, A19; ::_thesis: verum end; theorem Th60: :: LPSPACE2:60 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) let f, g be PartFunc of X,REAL; ::_thesis: for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) holds ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) let m, n be positive Real; ::_thesis: ( (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) implies ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) ) assume A1: ( (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,n) ) ; ::_thesis: ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) then A2: ( m > 1 & n > 1 ) by Th1; consider f1 being PartFunc of X,REAL such that A3: ( f = f1 & ex NDf being Element of S st ( M . (NDf `) = 0 & dom f1 = NDf & f1 is_measurable_on NDf & (abs f1) to_power m is_integrable_on M ) ) by A1; consider EDf being Element of S such that A4: ( M . (EDf `) = 0 & dom f1 = EDf & f1 is_measurable_on EDf ) by A3; consider g1 being PartFunc of X,REAL such that A5: ( g = g1 & ex NDg being Element of S st ( M . (NDg `) = 0 & dom g1 = NDg & g1 is_measurable_on NDg & (abs g1) to_power n is_integrable_on M ) ) by A1; consider EDg being Element of S such that A6: ( M . (EDg `) = 0 & dom g1 = EDg & g1 is_measurable_on EDg ) by A5; set u = (abs f1) to_power m; set v = (abs g1) to_power n; A7: ( 0 <= Integral (M,((abs f1) to_power m)) & 0 <= Integral (M,((abs g1) to_power n)) ) by A3, A5, A1, Th49; reconsider s1 = Integral (M,((abs f1) to_power m)), s2 = Integral (M,((abs g1) to_power n)) as Real by A3, A5, A1, Th49; A8: ( dom f1 = dom (abs f1) & dom g1 = dom (abs g1) ) by VALUED_1:def_11; reconsider Nf = EDf ` , Ng = EDg ` as Element of S by MEASURE1:34; set t1 = s1 to_power (1 / m); set t2 = s2 to_power (1 / n); set E = EDf /\ EDg; A9: (EDf /\ EDg) ` = (EDf `) \/ (EDg `) by XBOOLE_1:54; ( Nf is measure_zero of M & Ng is measure_zero of M ) by A4, A6, MEASURE1:def_7; then A10: (EDf /\ EDg) ` is measure_zero of M by A9, MEASURE1:37; A11: dom (f1 (#) g1) = EDf /\ EDg by A4, A6, VALUED_1:def_4; ( f1 is_measurable_on EDf /\ EDg & g1 is_measurable_on EDf /\ EDg ) by A4, A6, MESFUNC6:16, XBOOLE_1:17; then A12: f1 (#) g1 is_measurable_on EDf /\ EDg by A4, A6, MESFUN7C:31; A13: f1 (#) g1 in L1_Functions M by A1, A3, A5, Th59; then A14: ex fg1 being PartFunc of X,REAL st ( fg1 = f1 (#) g1 & ex ND being Element of S st ( M . ND = 0 & dom fg1 = ND ` & fg1 is_integrable_on M ) ) ; then A15: ( Integral (M,(abs (f1 (#) g1))) in REAL & abs (f1 (#) g1) is_integrable_on M ) by LPSPACE1:44; percases ( ( s1 = 0 & s2 >= 0 ) or ( s1 > 0 & s2 = 0 ) or ( s1 <> 0 & s2 <> 0 ) ) by A3, A5, A1, Th49; supposeA16: ( s1 = 0 & s2 >= 0 ) ; ::_thesis: ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) f1 in Lp_Functions (M,m) by A3; then f1 a.e.= X --> 0,M by A16, Th57; then consider Nf1 being Element of S such that A17: ( M . Nf1 = 0 & f1 | (Nf1 `) = (X --> 0) | (Nf1 `) ) by LPSPACE1:def_10; reconsider Z = ((EDf /\ EDg) \ Nf1) ` as Element of S by MEASURE1:34; A18: ((EDf /\ EDg) \ Nf1) ` = ((EDf /\ EDg) `) \/ Nf1 by SUBSET_1:14; Nf1 is measure_zero of M by A17, MEASURE1:def_7; then Z is measure_zero of M by A10, A18, MEASURE1:37; then A19: M . Z = 0 by MEASURE1:def_7; dom (X --> 0) = X by FUNCOP_1:13; then A20: dom ((X --> 0) | (Z `)) = Z ` by RELAT_1:62; A21: dom ((f1 (#) g1) | (Z `)) = Z ` by A11, RELAT_1:62, XBOOLE_1:36; for x being set st x in dom ((f1 (#) g1) | (Z `)) holds ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x proof let x be set ; ::_thesis: ( x in dom ((f1 (#) g1) | (Z `)) implies ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x ) assume A22: x in dom ((f1 (#) g1) | (Z `)) ; ::_thesis: ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x then ( x in X & not x in Nf1 ) by A21, XBOOLE_0:def_5; then x in Nf1 ` by XBOOLE_0:def_5; then ( f1 . x = (f1 | (Nf1 `)) . x & (X --> 0) . x = ((X --> 0) | (Nf1 `)) . x ) by FUNCT_1:49; then A23: f1 . x = 0 by A17, A22, FUNCOP_1:7; A24: dom ((f1 (#) g1) | (Z `)) c= dom (f1 (#) g1) by RELAT_1:60; ((f1 (#) g1) | (Z `)) . x = (f1 (#) g1) . x by A22, FUNCT_1:47 .= (f1 . x) * (g1 . x) by A22, A24, VALUED_1:def_4 .= ((Z `) --> 0) . x by A22, A21, A23, FUNCOP_1:7 .= ((X /\ (Z `)) --> 0) . x by XBOOLE_1:28 ; hence ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x by FUNCOP_1:12; ::_thesis: verum end; then (f1 (#) g1) | (Z `) = (X --> 0) | (Z `) by A20, A21, FUNCT_1:def_11; then A25: f1 (#) g1 a.e.= X --> 0,M by A19, LPSPACE1:def_10; X --> 0 in L1_Functions M by Th56; then Integral (M,(abs (f1 (#) g1))) = Integral (M,(abs (X --> 0))) by A13, A25, LPSPACE1:45; then A26: Integral (M,(abs (f1 (#) g1))) = 0 by LPSPACE1:54; (s1 to_power (1 / m)) * (s2 to_power (1 / n)) = 0 * (s2 to_power (1 / n)) by A16, POWER:def_2; hence ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) by A3, A5, A26; ::_thesis: verum end; supposeA27: ( s1 > 0 & s2 = 0 ) ; ::_thesis: ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) g1 in Lp_Functions (M,n) by A5; then g1 a.e.= X --> 0,M by A27, Th57; then consider Ng1 being Element of S such that A28: ( M . Ng1 = 0 & g1 | (Ng1 `) = (X --> 0) | (Ng1 `) ) by LPSPACE1:def_10; reconsider Z = ((EDf /\ EDg) \ Ng1) ` as Element of S by MEASURE1:34; A29: ((EDf /\ EDg) \ Ng1) ` = ((EDf /\ EDg) `) \/ Ng1 by SUBSET_1:14; Ng1 is measure_zero of M by A28, MEASURE1:def_7; then Z is measure_zero of M by A10, A29, MEASURE1:37; then A30: M . Z = 0 by MEASURE1:def_7; dom (X --> 0) = X by FUNCOP_1:13; then A31: dom ((X --> 0) | (Z `)) = Z ` by RELAT_1:62; A32: dom ((f1 (#) g1) | (Z `)) = Z ` by A11, RELAT_1:62, XBOOLE_1:36; for x being set st x in dom ((f1 (#) g1) | (Z `)) holds ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x proof let x be set ; ::_thesis: ( x in dom ((f1 (#) g1) | (Z `)) implies ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x ) assume A33: x in dom ((f1 (#) g1) | (Z `)) ; ::_thesis: ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x then ( x in X & not x in Ng1 ) by A32, XBOOLE_0:def_5; then x in Ng1 ` by XBOOLE_0:def_5; then ( g1 . x = (g1 | (Ng1 `)) . x & (X --> 0) . x = ((X --> 0) | (Ng1 `)) . x ) by FUNCT_1:49; then A34: g1 . x = 0 by A28, A33, FUNCOP_1:7; A35: dom ((f1 (#) g1) | (Z `)) c= dom (f1 (#) g1) by RELAT_1:60; ((f1 (#) g1) | (Z `)) . x = (f1 (#) g1) . x by A33, FUNCT_1:47 .= (f1 . x) * (g1 . x) by A33, A35, VALUED_1:def_4 .= ((Z `) --> 0) . x by A33, A32, A34, FUNCOP_1:7 .= ((X /\ (Z `)) --> 0) . x by XBOOLE_1:28 ; hence ((f1 (#) g1) | (Z `)) . x = ((X --> 0) | (Z `)) . x by FUNCOP_1:12; ::_thesis: verum end; then (f1 (#) g1) | (Z `) = (X --> 0) | (Z `) by A31, A32, FUNCT_1:def_11; then A36: f1 (#) g1 a.e.= X --> 0,M by A30, LPSPACE1:def_10; X --> 0 in L1_Functions M by Th56; then Integral (M,(abs (f1 (#) g1))) = Integral (M,(abs (X --> 0))) by A13, A36, LPSPACE1:45; then A37: Integral (M,(abs (f1 (#) g1))) = 0 by LPSPACE1:54; (s1 to_power (1 / m)) * (s2 to_power (1 / n)) = (s1 to_power (1 / m)) * 0 by A27, POWER:def_2; hence ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) by A3, A5, A37; ::_thesis: verum end; supposeA38: ( s1 <> 0 & s2 <> 0 ) ; ::_thesis: ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) then A39: ( s1 to_power (1 / m) > 0 & s2 to_power (1 / n) > 0 ) by A7, POWER:34; then A40: abs (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) = 1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))) by ABSVALUE:def_1; set w = (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1); set F = (1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m); set G = (1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n); set z = ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)); A41: ( dom ((1 / (s1 to_power (1 / m))) (#) (abs f1)) = dom (abs f1) & dom ((1 / (s2 to_power (1 / n))) (#) (abs g1)) = dom (abs g1) ) by VALUED_1:def_5; ( dom ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) = dom (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m) & dom ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) = dom (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n) ) by VALUED_1:def_5; then A42: ( dom ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) = dom (abs f1) & dom ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) = dom (abs g1) ) by A41, MESFUN6C:def_4; then A43: dom (((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) = (dom (abs f1)) /\ (dom (abs g1)) by VALUED_1:def_1; ( ((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m = ((1 / (s1 to_power (1 / m))) to_power m) (#) ((abs f1) to_power m) & ((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n = ((1 / (s2 to_power (1 / n))) to_power n) (#) ((abs g1) to_power n) ) by A39, Th19; then A44: ( ((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m is_integrable_on M & ((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n is_integrable_on M ) by A3, A5, MESFUNC6:102; then A45: ( (1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m) is_integrable_on M & (1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n) is_integrable_on M ) by MESFUNC6:102; then A46: ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) is_integrable_on M by MESFUNC6:100; A47: dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) = dom (f1 (#) g1) by VALUED_1:def_5; then A48: dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) = (dom f1) /\ (dom g1) by VALUED_1:def_4; dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (abs (f1 (#) g1))) = dom (abs (f1 (#) g1)) by VALUED_1:def_5; then A49: dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (abs (f1 (#) g1))) = dom (f1 (#) g1) by VALUED_1:def_11; A50: (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1) is_measurable_on EDf /\ EDg by A11, A12, MESFUNC6:21; for x being Element of X st x in dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) holds abs (((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) . x) <= (((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) . x proof let x be Element of X; ::_thesis: ( x in dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) implies abs (((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) . x) <= (((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) . x ) assume A51: x in dom ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) ; ::_thesis: abs (((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) . x) <= (((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) . x ( (abs f1) . x >= 0 & (abs g1) . x >= 0 ) by MESFUNC6:51; then A52: ((1 / (s1 to_power (1 / m))) * ((abs f1) . x)) * ((1 / (s2 to_power (1 / n))) * ((abs g1) . x)) <= ((((1 / (s1 to_power (1 / m))) * ((abs f1) . x)) to_power m) / m) + ((((1 / (s2 to_power (1 / n))) * ((abs g1) . x)) to_power n) / n) by A1, A2, A39, HOLDER_1:5; dom ((abs f1) (#) (abs g1)) = (dom (abs f1)) /\ (dom (abs g1)) by VALUED_1:def_4; then A53: ((abs f1) (#) (abs g1)) . x = ((abs f1) . x) * ((abs g1) . x) by A8, A48, A51, VALUED_1:def_4; A54: ((1 / (s1 to_power (1 / m))) * ((abs f1) . x)) * ((1 / (s2 to_power (1 / n))) * ((abs g1) . x)) = (((1 / (s1 to_power (1 / m))) * (1 / (s2 to_power (1 / n)))) * ((abs f1) . x)) * ((abs g1) . x) .= ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) * ((abs f1) . x)) * ((abs g1) . x) by XCMPLX_1:102 .= (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) * (((abs f1) (#) (abs g1)) . x) by A53 .= (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) * ((abs (f1 (#) g1)) . x) by RFUNCT_1:24 .= ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (abs (f1 (#) g1))) . x by A47, A51, A49, VALUED_1:def_5 .= (abs ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1))) . x by A40, RFUNCT_1:25 ; A55: ( (1 / (s1 to_power (1 / m))) * ((abs f1) . x) = ((1 / (s1 to_power (1 / m))) (#) (abs f1)) . x & (1 / (s2 to_power (1 / n))) * ((abs g1) . x) = ((1 / (s2 to_power (1 / n))) (#) (abs g1)) . x ) by VALUED_1:6; ( dom (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m) = dom f1 & dom (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n) = dom g1 ) by A8, A41, MESFUN6C:def_4; then ( x in dom (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m) & x in dom (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n) ) by A48, A51, XBOOLE_0:def_4; then ( (((1 / (s1 to_power (1 / m))) (#) (abs f1)) . x) to_power m = (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m) . x & (((1 / (s2 to_power (1 / n))) (#) (abs g1)) . x) to_power n = (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n) . x ) by MESFUN6C:def_4; then ( ((((1 / (s1 to_power (1 / m))) (#) (abs f1)) . x) to_power m) / m = ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) . x & ((((1 / (s2 to_power (1 / n))) (#) (abs g1)) . x) to_power n) / n = ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) . x ) by VALUED_1:6; then ((((1 / (s1 to_power (1 / m))) * ((abs f1) . x)) to_power m) / m) + ((((1 / (s2 to_power (1 / n))) * ((abs g1) . x)) to_power n) / n) = (((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) . x by A8, A48, A51, A43, A55, VALUED_1:def_1; hence abs (((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) . x) <= (((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) . x by A52, A54, VALUED_1:18; ::_thesis: verum end; then A56: Integral (M,(abs ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)))) <= Integral (M,(((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)))) by A4, A6, A46, A8, A48, A43, A50, MESFUNC6:96; A57: ex E1 being Element of S st ( E1 = (dom ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m))) /\ (dom ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) & Integral (M,(((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)))) = (Integral (M,(((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) | E1))) + (Integral (M,(((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) | E1))) ) by A45, MESFUNC6:101; ( EDf = X /\ EDf & EDg = X /\ EDg ) by XBOOLE_1:28; then A58: ( EDf = X \ Nf & EDg = X \ Ng ) by XBOOLE_1:48; A59: EDf \ (EDf /\ EDg) = EDf \ EDg by XBOOLE_1:47 .= ((X \ Nf) \ X) \/ ((X \ Nf) /\ Ng) by A58, XBOOLE_1:52 .= (X \ (Nf \/ X)) \/ ((X \ Nf) /\ Ng) by XBOOLE_1:41 .= (X \ X) \/ ((X \ Nf) /\ Ng) by XBOOLE_1:12 .= {} \/ ((X \ Nf) /\ Ng) by XBOOLE_1:37 ; A60: EDg \ (EDf /\ EDg) = EDg \ EDf by XBOOLE_1:47 .= ((X \ Ng) \ X) \/ ((X \ Ng) /\ Nf) by A58, XBOOLE_1:52 .= (X \ (Ng \/ X)) \/ ((X \ Ng) /\ Nf) by XBOOLE_1:41 .= (X \ X) \/ ((X \ Ng) /\ Nf) by XBOOLE_1:12 .= {} \/ ((X \ Ng) /\ Nf) by XBOOLE_1:37 ; set NF = EDf /\ Ng; set NG = EDg /\ Nf; ( Nf is measure_zero of M & Ng is measure_zero of M ) by A4, A6, MEASURE1:def_7; then ( EDf /\ Ng is measure_zero of M & EDg /\ Nf is measure_zero of M ) by MEASURE1:36, XBOOLE_1:17; then A61: ( M . (EDf /\ Ng) = 0 & M . (EDg /\ Nf) = 0 ) by MEASURE1:def_7; ( EDf /\ EDg = EDf /\ (EDf /\ EDg) & EDf /\ EDg = EDg /\ (EDf /\ EDg) ) by XBOOLE_1:17, XBOOLE_1:28; then A62: ( EDf /\ EDg = EDf \ (EDf /\ Ng) & EDf /\ EDg = EDg \ (EDg /\ Nf) ) by A58, A59, A60, XBOOLE_1:48; R_EAL ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) is_integrable_on M by A45, MESFUNC6:def_4; then ex E being Element of S st ( E = dom (R_EAL ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m))) & R_EAL ((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) is_measurable_on E ) by MESFUNC5:def_17; then A63: (1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m) is_measurable_on EDf by A42, A8, A4, MESFUNC6:def_1; R_EAL ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) is_integrable_on M by A45, MESFUNC6:def_4; then ex E being Element of S st ( E = dom (R_EAL ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) & R_EAL ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) is_measurable_on E ) by MESFUNC5:def_17; then A64: (1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n) is_measurable_on EDg by A42, A8, A6, MESFUNC6:def_1; (1 / (s1 to_power (1 / m))) to_power m = (s1 to_power (1 / m)) to_power (- m) by A38, A7, POWER:32, POWER:34; then (1 / (s1 to_power (1 / m))) to_power m = s1 to_power ((1 / m) * (- m)) by A7, A38, POWER:33; then (1 / (s1 to_power (1 / m))) to_power m = s1 to_power (- ((1 * (1 / m)) * m)) ; then (1 / (s1 to_power (1 / m))) to_power m = s1 to_power (- 1) by XCMPLX_1:106; then (1 / (s1 to_power (1 / m))) to_power m = (1 / s1) to_power 1 by A7, A38, POWER:32; then A65: (1 / (s1 to_power (1 / m))) to_power m = 1 / s1 by POWER:25; ( (R_EAL (1 / s1)) * (R_EAL s1) = (1 / s1) * s1 & (R_EAL (1 / s2)) * (R_EAL s2) = (1 / s2) * s2 ) by EXTREAL1:5; then A66: ( (R_EAL (1 / s1)) * (R_EAL s1) = 1 & (R_EAL (1 / s2)) * (R_EAL s2) = 1 ) by A38, XCMPLX_1:106; A67: (1 / (s2 to_power (1 / n))) to_power n = (s2 to_power (1 / n)) to_power (- n) by A38, A7, POWER:32, POWER:34 .= s2 to_power ((1 / n) * (- n)) by A7, A38, POWER:33 .= s2 to_power (- ((1 * (1 / n)) * n)) .= s2 to_power (- 1) by XCMPLX_1:106 .= (1 / s2) to_power 1 by A7, A38, POWER:32 .= 1 / s2 by POWER:25 ; A68: Integral (M,(((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) | (EDf /\ EDg))) = Integral (M,((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m))) by A4, A8, A42, A62, A61, A63, MESFUNC6:89 .= (R_EAL (1 / m)) * (Integral (M,(((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m))) by A44, MESFUNC6:102 .= (R_EAL (1 / m)) * (Integral (M,(((1 / (s1 to_power (1 / m))) to_power m) (#) ((abs f1) to_power m)))) by A39, Th19 .= (R_EAL (1 / m)) * ((R_EAL ((1 / (s1 to_power (1 / m))) to_power m)) * (Integral (M,((abs f1) to_power m)))) by A3, MESFUNC6:102 .= 1 / m by A65, A66, XXREAL_3:81 ; Integral (M,(((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)) | (EDf /\ EDg))) = Integral (M,((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) by A6, A8, A42, A62, A61, A64, MESFUNC6:89 .= (R_EAL (1 / n)) * (Integral (M,(((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n))) by A44, MESFUNC6:102 .= (R_EAL (1 / n)) * (Integral (M,(((1 / (s2 to_power (1 / n))) to_power n) (#) ((abs g1) to_power n)))) by A39, Th19 .= (R_EAL (1 / n)) * ((R_EAL ((1 / (s2 to_power (1 / n))) to_power n)) * (Integral (M,((abs g1) to_power n)))) by A5, MESFUNC6:102 .= 1 / n by A66, A67, XXREAL_3:81 ; then A69: Integral (M,(((1 / m) (#) (((1 / (s1 to_power (1 / m))) (#) (abs f1)) to_power m)) + ((1 / n) (#) (((1 / (s2 to_power (1 / n))) (#) (abs g1)) to_power n)))) = 1 by A1, A42, A4, A6, A8, A57, A68, SUPINF_2:1; abs ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) = (abs (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))))) (#) (abs (f1 (#) g1)) by RFUNCT_1:25; then abs ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)) = (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (abs (f1 (#) g1)) by A39, ABSVALUE:def_1; then A70: Integral (M,(abs ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) (#) (f1 (#) g1)))) = (R_EAL (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))))) * (Integral (M,(abs (f1 (#) g1)))) by A15, MESFUNC6:102; reconsider c1 = Integral (M,(abs (f1 (#) g1))) as Real by A14, LPSPACE1:44; (R_EAL (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))))) * (Integral (M,(abs (f1 (#) g1)))) = (R_EAL (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))))) * (R_EAL c1) ; then (R_EAL (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))))) * (Integral (M,(abs (f1 (#) g1)))) = (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) * c1 by EXTREAL1:5; then ((s1 to_power (1 / m)) * (s2 to_power (1 / n))) * ((1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) * c1) <= ((s1 to_power (1 / m)) * (s2 to_power (1 / n))) * 1 by A39, A56, A70, A69, XREAL_1:64; then A71: (((s1 to_power (1 / m)) * (s2 to_power (1 / n))) * (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n))))) * c1 <= (s1 to_power (1 / m)) * (s2 to_power (1 / n)) ; ((s1 to_power (1 / m)) * (s2 to_power (1 / n))) * (1 / ((s1 to_power (1 / m)) * (s2 to_power (1 / n)))) = 1 by A39, XCMPLX_1:106; hence ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power n)) & Integral (M,(abs (f (#) g))) <= (r1 to_power (1 / m)) * (r2 to_power (1 / n)) ) ) by A3, A5, A71; ::_thesis: verum end; end; end; Lm5: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) holds ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) holds ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) holds ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) holds ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) let f, g be PartFunc of X,REAL; ::_thesis: for m, n being positive Real st (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) holds ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) let m, n be positive Real; ::_thesis: ( (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) implies ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) ) assume A1: ( (1 / m) + (1 / n) = 1 & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) ) ; ::_thesis: ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) then ((m + n) * ((m * n) ")) * (m * n) = 1 * (m * n) by XCMPLX_1:211; then (m + n) * (((m * n) ") * (m * n)) = m * n ; then (m + n) * 1 = m * n by XCMPLX_0:def_7; then A2: m = n * (m - 1) ; A3: 1 - 1 < m - 1 by A1, Th1, XREAL_1:14; then A4: m - 1 > 0 ; ex f1 being PartFunc of X,REAL st ( f = f1 & ex NDf being Element of S st ( M . (NDf `) = 0 & dom f1 = NDf & f1 is_measurable_on NDf & (abs f1) to_power m is_integrable_on M ) ) by A1; then consider EDf being Element of S such that A5: ( M . (EDf `) = 0 & dom f = EDf & f is_measurable_on EDf ) ; ex g1 being PartFunc of X,REAL st ( g = g1 & ex NDg being Element of S st ( M . (NDg `) = 0 & dom g1 = NDg & g1 is_measurable_on NDg & (abs g1) to_power m is_integrable_on M ) ) by A1; then consider EDg being Element of S such that A6: ( M . (EDg `) = 0 & dom g = EDg & g is_measurable_on EDg ) ; set E = EDf /\ EDg; A7: f + g in Lp_Functions (M,m) by A1, Th25; then A8: ex h1 being PartFunc of X,REAL st ( f + g = h1 & ex NDfg being Element of S st ( M . (NDfg `) = 0 & dom h1 = NDfg & h1 is_measurable_on NDfg & (abs h1) to_power m is_integrable_on M ) ) ; A9: dom (f + g) = EDf /\ EDg by A5, A6, VALUED_1:def_1; then A10: abs (f + g) is_measurable_on EDf /\ EDg by A8, MESFUNC6:48; reconsider s1 = Integral (M,((abs f) to_power m)) as Real by A1, Th49; reconsider s2 = Integral (M,((abs g) to_power m)) as Real by A1, Th49; reconsider s3 = Integral (M,((abs (f + g)) to_power m)) as Real by A7, Th49; set t = (abs (f + g)) to_power (m - 1); A11: dom ((abs (f + g)) to_power (m - 1)) = dom (abs (f + g)) by MESFUN6C:def_4; then A12: dom ((abs (f + g)) to_power (m - 1)) = EDf /\ EDg by A9, VALUED_1:def_11; then A13: (abs (f + g)) to_power (m - 1) is_measurable_on EDf /\ EDg by A3, A10, A11, MESFUN6C:29; A14: ((abs (f + g)) to_power (m - 1)) to_power n = (abs (f + g)) to_power m by A2, A3, Th6; A15: abs ((abs (f + g)) to_power (m - 1)) = (abs (f + g)) to_power (m - 1) by Th14, A4; then A16: (abs (f + g)) to_power (m - 1) in Lp_Functions (M,n) by A9, A12, A14, A8, A13; then reconsider s4 = Integral (M,((abs ((abs (f + g)) to_power (m - 1))) to_power n)) as Real by Th49; ( ((abs (f + g)) to_power (m - 1)) (#) f is_integrable_on M & ((abs (f + g)) to_power (m - 1)) (#) g is_integrable_on M ) by A1, A16, Th59; then reconsider u1 = Integral (M,(abs (((abs (f + g)) to_power (m - 1)) (#) f))), u2 = Integral (M,(abs (((abs (f + g)) to_power (m - 1)) (#) g))) as Real by LPSPACE1:44; A17: ( dom (abs f) = EDf & dom (abs g) = EDg ) by A5, A6, VALUED_1:def_11; ( dom (((abs (f + g)) to_power (m - 1)) (#) (abs f)) = (dom ((abs (f + g)) to_power (m - 1))) /\ (dom (abs f)) & dom (((abs (f + g)) to_power (m - 1)) (#) (abs g)) = (dom ((abs (f + g)) to_power (m - 1))) /\ (dom (abs g)) ) by VALUED_1:def_4; then A18: ( dom (((abs (f + g)) to_power (m - 1)) (#) (abs f)) = EDf /\ EDg & dom (((abs (f + g)) to_power (m - 1)) (#) (abs g)) = EDf /\ EDg ) by A12, A17, XBOOLE_1:17, XBOOLE_1:28; A19: ( abs (((abs (f + g)) to_power (m - 1)) (#) f) = ((abs (f + g)) to_power (m - 1)) (#) (abs f) & abs (((abs (f + g)) to_power (m - 1)) (#) g) = ((abs (f + g)) to_power (m - 1)) (#) (abs g) & abs (((abs (f + g)) to_power (m - 1)) (#) (f + g)) = ((abs (f + g)) to_power (m - 1)) (#) (abs (f + g)) ) by A15, RFUNCT_1:24; ( ((abs (f + g)) to_power (m - 1)) (#) f is_integrable_on M & ((abs (f + g)) to_power (m - 1)) (#) g is_integrable_on M & ((abs (f + g)) to_power (m - 1)) (#) (f + g) is_integrable_on M ) by A1, A16, A7, Th59; then A20: ( ((abs (f + g)) to_power (m - 1)) (#) (abs f) is_integrable_on M & ((abs (f + g)) to_power (m - 1)) (#) (abs g) is_integrable_on M & ((abs (f + g)) to_power (m - 1)) (#) (abs (f + g)) is_integrable_on M ) by A19, LPSPACE1:44; set F = ((abs (f + g)) to_power (m - 1)) (#) (abs (f + g)); set G = (((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g)); A21: dom (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) = (EDf /\ EDg) /\ (EDf /\ EDg) by A11, A12, VALUED_1:def_4; A22: dom ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g))) = (EDf /\ EDg) /\ (EDf /\ EDg) by A18, VALUED_1:def_1; R_EAL (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) is_integrable_on M by A20, MESFUNC6:def_4; then ex E1 being Element of S st ( E1 = dom (R_EAL (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g)))) & R_EAL (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) is_measurable_on E1 ) by MESFUNC5:def_17; then A23: ((abs (f + g)) to_power (m - 1)) (#) (abs (f + g)) is_measurable_on EDf /\ EDg by A21, MESFUNC6:def_1; A24: (((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g)) is_integrable_on M by A20, MESFUNC6:100; for x being Element of X st x in dom (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) holds abs ((((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) . x) <= ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g))) . x proof let x be Element of X; ::_thesis: ( x in dom (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) implies abs ((((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) . x) <= ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g))) . x ) assume A25: x in dom (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) ; ::_thesis: abs ((((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) . x) <= ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g))) . x then abs ((f . x) + (g . x)) = abs ((f + g) . x) by A9, A21, VALUED_1:def_1; then A26: ( abs ((f . x) + (g . x)) = (abs (f + g)) . x & abs (f . x) = (abs f) . x & abs (g . x) = (abs g) . x ) by VALUED_1:18; (R_EAL (f . x)) + (R_EAL (g . x)) = (f . x) + (g . x) by SUPINF_2:1; then A27: ( |.(R_EAL (f . x)).| = abs (f . x) & |.(R_EAL (g . x)).| = abs (g . x) & |.((R_EAL (f . x)) + (R_EAL (g . x))).| = abs ((f . x) + (g . x)) ) by EXTREAL2:1; A28: ( ((abs (f + g)) to_power (m - 1)) . x >= 0 & (abs (f + g)) . x >= 0 ) by A3, MESFUNC6:51; |.((R_EAL (f . x)) + (R_EAL (g . x))).| <= |.(R_EAL (f . x)).| + |.(R_EAL (g . x)).| by EXTREAL2:13; then abs ((f . x) + (g . x)) <= (abs (f . x)) + (abs (g . x)) by A27, SUPINF_2:1; then A29: (((abs (f + g)) to_power (m - 1)) . x) * ((abs (f + g)) . x) <= (((abs (f + g)) to_power (m - 1)) . x) * (((abs f) . x) + ((abs g) . x)) by A26, A28, XREAL_1:64; ( (((abs (f + g)) to_power (m - 1)) . x) * ((abs f) . x) = (((abs (f + g)) to_power (m - 1)) (#) (abs f)) . x & (((abs (f + g)) to_power (m - 1)) . x) * ((abs g) . x) = (((abs (f + g)) to_power (m - 1)) (#) (abs g)) . x ) by VALUED_1:5; then (((abs (f + g)) to_power (m - 1)) . x) * (((abs f) . x) + ((abs g) . x)) = ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) . x) + ((((abs (f + g)) to_power (m - 1)) (#) (abs g)) . x) ; then A30: (((abs (f + g)) to_power (m - 1)) . x) * (((abs f) . x) + ((abs g) . x)) = ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g))) . x by A21, A22, A25, VALUED_1:def_1; (((abs (f + g)) to_power (m - 1)) . x) * ((abs (f + g)) . x) = (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) . x by VALUED_1:5; hence abs ((((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))) . x) <= ((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g))) . x by A30, A29, A28, ABSVALUE:def_1; ::_thesis: verum end; then A31: Integral (M,(abs (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))))) <= Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g)))) by A21, A22, A23, A24, MESFUNC6:96; A32: ex E1 being Element of S st ( E1 = (EDf /\ EDg) /\ (EDf /\ EDg) & Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g)))) = (Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs f)) | E1))) + (Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs g)) | E1))) ) by A18, A20, MESFUNC6:101; ( Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs f)) | (EDf /\ EDg))) = Integral (M,(((abs (f + g)) to_power (m - 1)) (#) (abs f))) & Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs g)) | (EDf /\ EDg))) = Integral (M,(((abs (f + g)) to_power (m - 1)) (#) (abs g))) ) by A18, RELAT_1:69; then A33: Integral (M,((((abs (f + g)) to_power (m - 1)) (#) (abs f)) + (((abs (f + g)) to_power (m - 1)) (#) (abs g)))) = u1 + u2 by A19, A32, SUPINF_2:1; set v1 = (s4 to_power (1 / n)) * (s1 to_power (1 / m)); set v2 = (s4 to_power (1 / n)) * (s2 to_power (1 / m)); ( ex r4 being Real st ( r4 = Integral (M,((abs ((abs (f + g)) to_power (m - 1))) to_power n)) & ex r1 being Real st ( r1 = Integral (M,((abs f) to_power m)) & Integral (M,(abs (((abs (f + g)) to_power (m - 1)) (#) f))) <= (r4 to_power (1 / n)) * (r1 to_power (1 / m)) ) ) & ex r4 being Real st ( r4 = Integral (M,((abs ((abs (f + g)) to_power (m - 1))) to_power n)) & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power m)) & Integral (M,(abs (((abs (f + g)) to_power (m - 1)) (#) g))) <= (r4 to_power (1 / n)) * (r2 to_power (1 / m)) ) ) ) by A1, A16, Th60; then A34: u1 + u2 <= ((s4 to_power (1 / n)) * (s1 to_power (1 / m))) + ((s4 to_power (1 / n)) * (s2 to_power (1 / m))) by XREAL_1:7; ((abs (f + g)) to_power (m - 1)) (#) (abs (f + g)) = ((abs (f + g)) to_power (m - 1)) (#) ((abs (f + g)) to_power 1) by Th8 .= (abs (f + g)) to_power ((m - 1) + 1) by Th7, A3 ; then Integral (M,(abs (((abs (f + g)) to_power (m - 1)) (#) (abs (f + g))))) = s3 by Th14; then A35: s3 <= ((s3 to_power (1 / n)) * (s1 to_power (1 / m))) + ((s3 to_power (1 / n)) * (s2 to_power (1 / m))) by A14, A15, A31, A33, A34, XXREAL_0:2; percases ( s3 = 0 or s3 > 0 ) by A7, Th49; suppose s3 = 0 ; ::_thesis: ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) then A36: s3 to_power (1 / m) = 0 by POWER:def_2; ( s1 to_power (1 / m) >= 0 & s2 to_power (1 / m) >= 0 ) by A1, Th49, Th4; then s3 to_power (1 / m) <= (s1 to_power (1 / m)) + (s2 to_power (1 / m)) by A36; hence ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) ; ::_thesis: verum end; supposeA37: s3 > 0 ; ::_thesis: ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) then A38: s3 to_power (1 / n) > 0 by POWER:34; set w1 = s3 to_power (1 / n); (1 / (s3 to_power (1 / n))) * (((s3 to_power (1 / n)) * (s1 to_power (1 / m))) + ((s3 to_power (1 / n)) * (s2 to_power (1 / m)))) = ((1 / (s3 to_power (1 / n))) * (s3 to_power (1 / n))) * ((s1 to_power (1 / m)) + (s2 to_power (1 / m))) ; then A39: (1 / (s3 to_power (1 / n))) * (((s3 to_power (1 / n)) * (s1 to_power (1 / m))) + ((s3 to_power (1 / n)) * (s2 to_power (1 / m)))) = 1 * ((s1 to_power (1 / m)) + (s2 to_power (1 / m))) by A38, XCMPLX_1:106; (1 / (s3 to_power (1 / n))) * s3 = (s3 to_power (- (1 / n))) * s3 by A37, POWER:28 .= (s3 to_power (- (1 / n))) * (s3 to_power 1) by POWER:25 .= s3 to_power ((- (1 / n)) + 1) by A37, POWER:27 .= s3 to_power (1 / m) by A1 ; hence ex r1, r2, r3 being Real st ( r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) & r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) by A38, A39, A35, XREAL_1:64; ::_thesis: verum end; end; end; theorem Th61: :: LPSPACE2:61 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m being positive Real for r1, r2, r3 being Element of REAL st 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) holds r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m being positive Real for r1, r2, r3 being Element of REAL st 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) holds r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f, g being PartFunc of X,REAL for m being positive Real for r1, r2, r3 being Element of REAL st 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) holds r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) let M be sigma_Measure of S; ::_thesis: for f, g being PartFunc of X,REAL for m being positive Real for r1, r2, r3 being Element of REAL st 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) holds r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) let f, g be PartFunc of X,REAL; ::_thesis: for m being positive Real for r1, r2, r3 being Element of REAL st 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) holds r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) let m be positive Real; ::_thesis: for r1, r2, r3 being Element of REAL st 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) holds r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) let r1, r2, r3 be Element of REAL ; ::_thesis: ( 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) implies r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) ) assume A1: ( 1 <= m & f in Lp_Functions (M,m) & g in Lp_Functions (M,m) & r1 = Integral (M,((abs f) to_power m)) & r2 = Integral (M,((abs g) to_power m)) & r3 = Integral (M,((abs (f + g)) to_power m)) ) ; ::_thesis: r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) percases ( m = 1 or m <> 1 ) ; supposeA2: m = 1 ; ::_thesis: r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) then A3: ( r1 = Integral (M,(abs f)) & r2 = Integral (M,(abs g)) & r3 = Integral (M,(abs (f + g))) ) by A1, Th8; A4: ex f1 being PartFunc of X,REAL st ( f = f1 & ex ND being Element of S st ( M . (ND `) = 0 & dom f1 = ND & f1 is_measurable_on ND & (abs f1) to_power m is_integrable_on M ) ) by A1; A5: ex g1 being PartFunc of X,REAL st ( g = g1 & ex ND being Element of S st ( M . (ND `) = 0 & dom g1 = ND & g1 is_measurable_on ND & (abs g1) to_power m is_integrable_on M ) ) by A1; then ( abs f is_integrable_on M & abs g is_integrable_on M ) by A2, A4, Th8; then ( f is_integrable_on M & g is_integrable_on M ) by A4, A5, MESFUNC6:94; then Integral (M,(abs (f + g))) <= (Integral (M,(abs f))) + (Integral (M,(abs g))) by LPSPACE1:55; then A6: r3 <= r1 + r2 by A3, XXREAL_3:def_2; ( r1 to_power (1 / m) = r1 & r2 to_power (1 / m) = r2 ) by A2, POWER:25; hence r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) by A6, A2, POWER:25; ::_thesis: verum end; supposeA7: m <> 1 ; ::_thesis: r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) set n1 = 1 - (1 / m); 1 < m by A1, A7, XXREAL_0:1; then 1 / m < 1 by XREAL_1:189; then 0 < 1 - (1 / m) by XREAL_1:50; then reconsider n = 1 / (1 - (1 / m)) as positive Real ; (1 / m) + (1 / n) = 1 ; then ex rr1, rr2, rr3 being Real st ( rr1 = Integral (M,((abs f) to_power m)) & rr2 = Integral (M,((abs g) to_power m)) & rr3 = Integral (M,((abs (f + g)) to_power m)) & rr3 to_power (1 / m) <= (rr1 to_power (1 / m)) + (rr2 to_power (1 / m)) ) by A1, Lm5; hence r3 to_power (1 / m) <= (r1 to_power (1 / m)) + (r2 to_power (1 / m)) by A1; ::_thesis: verum end; end; end; Lm6: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being geq_than_1 Real holds ( Lp-Space (M,k) is reflexive & Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being geq_than_1 Real holds ( Lp-Space (M,k) is reflexive & Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being geq_than_1 Real holds ( Lp-Space (M,k) is reflexive & Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) let M be sigma_Measure of S; ::_thesis: for k being geq_than_1 Real holds ( Lp-Space (M,k) is reflexive & Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) let k be geq_than_1 Real; ::_thesis: ( Lp-Space (M,k) is reflexive & Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) set x = 0. (Lp-Space (M,k)); 0. (Lp-Space (M,k)) = 0. (Pre-Lp-Space (M,k)) ; then 0. (Lp-Space (M,k)) = zeroCoset (M,k) by Def11; then X --> 0 in 0. (Lp-Space (M,k)) by Th38, Th23; then ex r being Real st ( 0 <= r & r = Integral (M,((abs (X --> 0)) to_power k)) & ||.(0. (Lp-Space (M,k))).|| = r to_power (1 / k) ) by Th55; then consider r0 being Real such that A1: ( r0 = Integral (M,((abs (X --> 0)) to_power k)) & (Lp-Norm (M,k)) . (0. (Lp-Space (M,k))) = r0 to_power (1 / k) ) ; r0 = 0 by A1, Th58; hence ||.(0. (Lp-Space (M,k))).|| = 0 by A1, POWER:def_2; :: according to NORMSP_0:def_6 ::_thesis: ( Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) now__::_thesis:_for_x,_y_being_Point_of_(Lp-Space_(M,k)) for_a_being_Real_holds_ (_(_||.x.||_=_0_implies_x_=_0._(Lp-Space_(M,k))_)_&_0_<=_||.x.||_&_||.(x_+_y).||_<=_||.x.||_+_||.y.||_&_||.(a_*_x).||_=_(abs_a)_*_||.x.||_) let x, y be Point of (Lp-Space (M,k)); ::_thesis: for a being Real holds ( ( ||.x.|| = 0 implies x = 0. (Lp-Space (M,k)) ) & 0 <= ||.x.|| & ||.(x + y).|| <= ||.x.|| + ||.y.|| & ||.(a * x).|| = (abs a) * ||.x.|| ) let a be Real; ::_thesis: ( ( ||.x.|| = 0 implies x = 0. (Lp-Space (M,k)) ) & 0 <= ||.x.|| & ||.(x + y).|| <= ||.x.|| + ||.y.|| & ||.(a * x).|| = (abs a) * ||.x.|| ) A2: 1 <= k by Def1; hereby ::_thesis: ( 0 <= ||.x.|| & ||.(x + y).|| <= ||.x.|| + ||.y.|| & ||.(a * x).|| = (abs a) * ||.x.|| ) assume A3: ||.x.|| = 0 ; ::_thesis: x = 0. (Lp-Space (M,k)) consider f being PartFunc of X,REAL such that A4: ( f in x & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & ||.x.|| = r to_power (1 / k) ) ) by Def12; A5: f in Lp_Functions (M,k) by Th51, A4; then consider r1 being Real such that A6: ( r1 = Integral (M,((abs f) to_power k)) & r1 >= 0 & (Lp-Norm (M,k)) . x = r1 to_power (1 / k) ) by A4, Th49; r1 = 0 by A3, A6, POWER:34; then zeroCoset (M,k) = a.e-eq-class_Lp (f,M,k) by A5, A6, Th57, Th42; then 0. (Pre-Lp-Space (M,k)) = a.e-eq-class_Lp (f,M,k) by Def11; hence x = 0. (Lp-Space (M,k)) by A4, Th55; ::_thesis: verum end; consider f being PartFunc of X,REAL such that A7: ( f in x & ex r1 being Real st ( r1 = Integral (M,((abs f) to_power k)) & ||.x.|| = r1 to_power (1 / k) ) ) by Def12; A8: ( (abs f) to_power k is_integrable_on M & f in Lp_Functions (M,k) ) by Th51, A7; consider g being PartFunc of X,REAL such that A9: ( g in y & ex r2 being Real st ( r2 = Integral (M,((abs g) to_power k)) & ||.y.|| = r2 to_power (1 / k) ) ) by Def12; A10: ( (abs g) to_power k is_integrable_on M & g in Lp_Functions (M,k) ) by Th51, A9; consider s1 being Real such that A11: ( s1 = Integral (M,((abs f) to_power k)) & ||.x.|| = s1 to_power (1 / k) ) by A7; A12: ( s1 = 0 implies s1 to_power (1 / k) >= 0 ) by POWER:def_2; ( s1 > 0 implies s1 to_power (1 / k) >= 0 ) by POWER:34; hence 0 <= ||.x.|| by A12, A8, A11, Th49; ::_thesis: ( ||.(x + y).|| <= ||.x.|| + ||.y.|| & ||.(a * x).|| = (abs a) * ||.x.|| ) set t = f + g; set w = x + y; A13: s1 >= 0 by A8, A11, Th49; consider s2 being Real such that A14: ( s2 = Integral (M,((abs g) to_power k)) & ||.y.|| = s2 to_power (1 / k) ) by A9; f + g in x + y by Th54, A7, A9; then ex r being Real st ( 0 <= r & r = Integral (M,((abs (f + g)) to_power k)) & ||.(x + y).|| = r to_power (1 / k) ) by Th53; hence ||.(x + y).|| <= ||.x.|| + ||.y.|| by Th61, A2, A8, A10, A14, A11; ::_thesis: ||.(a * x).|| = (abs a) * ||.x.|| set t = a (#) f; set w = a * x; a (#) f in a * x by Th54, A7; then ex r being Real st ( 0 <= r & r = Integral (M,((abs (a (#) f)) to_power k)) & ||.(a * x).|| = r to_power (1 / k) ) by Th53; then consider s being Real such that A15: ( s = Integral (M,((abs (a (#) f)) to_power k)) & ||.(a * x).|| = s to_power (1 / k) ) ; A16: s = Integral (M,(((abs a) to_power k) (#) ((abs f) to_power k))) by A15, Th18 .= (R_EAL ((abs a) to_power k)) * (R_EAL s1) by A11, A8, MESFUNC6:102 .= ((abs a) to_power k) * s1 by EXTREAL1:5 ; (abs a) to_power k >= 0 by Th4, COMPLEX1:46; then ||.(a * x).|| = (((abs a) to_power k) to_power (1 / k)) * (s1 to_power (1 / k)) by A13, A15, A16, Th5 .= ((abs a) to_power (k * (1 / k))) * (s1 to_power (1 / k)) by COMPLEX1:46, HOLDER_1:2 .= ((abs a) to_power 1) * (s1 to_power (1 / k)) by XCMPLX_1:106 ; hence ||.(a * x).|| = (abs a) * ||.x.|| by A11, POWER:25; ::_thesis: verum end; hence ( Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) by NORMSP_0:def_5, NORMSP_1:def_1, RSSPACE3:2; ::_thesis: verum end; registration let k be geq_than_1 Real; let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; cluster Lp-Space (M,k) -> non empty right_complementable Abelian add-associative right_zeroed vector-distributive scalar-distributive scalar-associative scalar-unital discerning reflexive RealNormSpace-like ; coherence ( Lp-Space (M,k) is reflexive & Lp-Space (M,k) is discerning & Lp-Space (M,k) is RealNormSpace-like & Lp-Space (M,k) is vector-distributive & Lp-Space (M,k) is scalar-distributive & Lp-Space (M,k) is scalar-associative & Lp-Space (M,k) is scalar-unital & Lp-Space (M,k) is Abelian & Lp-Space (M,k) is add-associative & Lp-Space (M,k) is right_zeroed & Lp-Space (M,k) is right_complementable ) by Lm6; end; begin theorem Th62: :: LPSPACE2:62 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let M be sigma_Measure of S; ::_thesis: for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let k be positive Real; ::_thesis: for Sq being sequence of (Lp-Space (M,k)) ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let Sq be sequence of (Lp-Space (M,k)); ::_thesis: ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) defpred S1[ Element of NAT , set ] means ex f being PartFunc of X,REAL st ( $2 = f & f in Lp_Functions (M,k) & f in Sq . $1 & Sq . $1 = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & ||.(Sq . $1).|| = r to_power (1 / k) ) ); A1: for x being Element of NAT ex y being Element of PFuncs (X,REAL) st S1[x,y] proof let x be Element of NAT ; ::_thesis: ex y being Element of PFuncs (X,REAL) st S1[x,y] consider y being PartFunc of X,REAL such that A2: ( y in Lp_Functions (M,k) & Sq . x = a.e-eq-class_Lp (y,M,k) ) by Th53; ex r being Real st ( 0 <= r & r = Integral (M,((abs y) to_power k)) & ||.(Sq . x).|| = r to_power (1 / k) ) by Th53, A2, Th38; hence ex y being Element of PFuncs (X,REAL) st S1[x,y] by A2, Th38; ::_thesis: verum end; consider G being Function of NAT,(PFuncs (X,REAL)) such that A3: for n being Element of NAT holds S1[n,G . n] from FUNCT_2:sch_3(A1); reconsider G = G as Functional_Sequence of X,REAL ; now__::_thesis:_for_n_being_Element_of_NAT_holds_ (_G_._n_in_Lp_Functions_(M,k)_&_G_._n_in_Sq_._n_&_Sq_._n_=_a.e-eq-class_Lp_((G_._n),M,k)_&_ex_r_being_Real_st_ (_r_=_Integral_(M,((abs_(G_._n))_to_power_k))_&_||.(Sq_._n).||_=_r_to_power_(1_/_k)_)_) let n be Element of NAT ; ::_thesis: ( G . n in Lp_Functions (M,k) & G . n in Sq . n & Sq . n = a.e-eq-class_Lp ((G . n),M,k) & ex r being Real st ( r = Integral (M,((abs (G . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) ex f being PartFunc of X,REAL st ( G . n = f & f in Lp_Functions (M,k) & f in Sq . n & Sq . n = a.e-eq-class_Lp (f,M,k) & ex r being Real st ( r = Integral (M,((abs f) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) by A3; hence ( G . n in Lp_Functions (M,k) & G . n in Sq . n & Sq . n = a.e-eq-class_Lp ((G . n),M,k) & ex r being Real st ( r = Integral (M,((abs (G . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) ; ::_thesis: verum end; hence ex Fsq being Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) ; ::_thesis: verum end; theorem Th63: :: LPSPACE2:63 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being with_the_same_dom Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being with_the_same_dom Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being with_the_same_dom Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let M be sigma_Measure of S; ::_thesis: for k being positive Real for Sq being sequence of (Lp-Space (M,k)) ex Fsq being with_the_same_dom Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let k be positive Real; ::_thesis: for Sq being sequence of (Lp-Space (M,k)) ex Fsq being with_the_same_dom Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) let Sq be sequence of (Lp-Space (M,k)); ::_thesis: ex Fsq being with_the_same_dom Functional_Sequence of X,REAL st for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) consider Fsq being Functional_Sequence of X,REAL such that A1: for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) by Th62; defpred S1[ Element of NAT , set ] means ex DMFSQN being Element of S st ( $2 = DMFSQN & ex FSQN being PartFunc of X,REAL st ( Fsq . $1 = FSQN & M . (DMFSQN `) = 0 & dom FSQN = DMFSQN & FSQN is_measurable_on DMFSQN & (abs FSQN) to_power k is_integrable_on M ) ); A2: for n being Element of NAT ex y being Element of S st S1[n,y] proof let n be Element of NAT ; ::_thesis: ex y being Element of S st S1[n,y] Fsq . n in Lp_Functions (M,k) by A1; then ex FMF being PartFunc of X,REAL st ( Fsq . n = FMF & ex ND being Element of S st ( M . (ND `) = 0 & dom FMF = ND & FMF is_measurable_on ND & (abs FMF) to_power k is_integrable_on M ) ) ; hence ex y being Element of S st S1[n,y] ; ::_thesis: verum end; consider G being Function of NAT,S such that A3: for n being Element of NAT holds S1[n,G . n] from FUNCT_2:sch_3(A2); reconsider E0 = meet (rng G) as Element of S ; A4: for n being Element of NAT holds ( M . (X \ (G . n)) = 0 & E0 c= dom (Fsq . n) ) proof let n be Element of NAT ; ::_thesis: ( M . (X \ (G . n)) = 0 & E0 c= dom (Fsq . n) ) ex D being Element of S st ( G . n = D & ex F being PartFunc of X,REAL st ( Fsq . n = F & M . (D `) = 0 & dom F = D & F is_measurable_on D & (abs F) to_power k is_integrable_on M ) ) by A3; hence ( M . (X \ (G . n)) = 0 & E0 c= dom (Fsq . n) ) by FUNCT_2:4, SETFAM_1:3; ::_thesis: verum end; A5: X \ (rng G) is N_Sub_set_fam of X by MEASURE1:21; for A being set st A in X \ (rng G) holds ( A in S & A is measure_zero of M ) proof let A be set ; ::_thesis: ( A in X \ (rng G) implies ( A in S & A is measure_zero of M ) ) assume A6: A in X \ (rng G) ; ::_thesis: ( A in S & A is measure_zero of M ) then reconsider A0 = A as Subset of X ; A0 ` in rng G by A6, SETFAM_1:def_7; then consider n being set such that A7: ( n in NAT & A0 ` = G . n ) by FUNCT_2:11; reconsider n = n as Element of NAT by A7; A8: (A0 `) ` = A0 ; then A0 = X \ (G . n) by A7; hence A in S by MEASURE1:34; ::_thesis: A is measure_zero of M A9: M . A0 = 0 by A4, A7, A8; A0 = X \ (G . n) by A7, A8; then A is Element of S by MEASURE1:34; hence A is measure_zero of M by A9, MEASURE1:def_7; ::_thesis: verum end; then A10: ( ( for A being set st A in X \ (rng G) holds A in S ) & ( for A being set st A in X \ (rng G) holds A is measure_zero of M ) ) ; then X \ (rng G) c= S by TARSKI:def_3; then X \ (rng G) is N_Measure_fam of S by A5, MEASURE2:def_1; then A11: union (X \ (rng G)) is measure_zero of M by A10, MEASURE2:14; E0 ` = X \ (X \ (union (X \ (rng G)))) by MEASURE1:4 .= X /\ (union (X \ (rng G))) by XBOOLE_1:48 .= union (X \ (rng G)) by XBOOLE_1:28 ; then A12: M . (E0 `) = 0 by A11, MEASURE1:def_7; set Fsq2 = Fsq || E0; A13: for n being Element of NAT holds dom ((Fsq || E0) . n) = E0 proof let n be Element of NAT ; ::_thesis: dom ((Fsq || E0) . n) = E0 dom ((Fsq || E0) . n) = dom ((Fsq . n) | E0) by MESFUN9C:def_1; then dom ((Fsq || E0) . n) = (dom (Fsq . n)) /\ E0 by RELAT_1:61; hence dom ((Fsq || E0) . n) = E0 by A4, XBOOLE_1:28; ::_thesis: verum end; now__::_thesis:_for_n,_m_being_Nat_holds_dom_((Fsq_||_E0)_._n)_=_dom_((Fsq_||_E0)_._m) let n, m be Nat; ::_thesis: dom ((Fsq || E0) . n) = dom ((Fsq || E0) . m) ( n is Element of NAT & m is Element of NAT ) by ORDINAL1:def_12; then ( dom ((Fsq || E0) . n) = E0 & dom ((Fsq || E0) . m) = E0 ) by A13; hence dom ((Fsq || E0) . n) = dom ((Fsq || E0) . m) ; ::_thesis: verum end; then reconsider Fsq2 = Fsq || E0 as with_the_same_dom Functional_Sequence of X,REAL by MESFUNC8:def_2; take Fsq2 ; ::_thesis: for n being Element of NAT holds ( Fsq2 . n in Lp_Functions (M,k) & Fsq2 . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq2 . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq2 . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) hereby ::_thesis: verum let n be Element of NAT ; ::_thesis: ( Fsq2 . n in Lp_Functions (M,k) & Fsq2 . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq2 . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq2 . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) Fsq . n in Lp_Functions (M,k) by A1; then A14: ex FMF being PartFunc of X,REAL st ( Fsq . n = FMF & ex ND being Element of S st ( M . (ND `) = 0 & dom FMF = ND & FMF is_measurable_on ND & (abs FMF) to_power k is_integrable_on M ) ) ; then reconsider E2 = dom (Fsq . n) as Element of S ; A15: E2 /\ E0 = E0 by A4, XBOOLE_1:28; R_EAL (Fsq . n) is_measurable_on E2 by A14, MESFUNC6:def_1; then R_EAL (Fsq . n) is_measurable_on E0 by A4, MESFUNC1:30; then Fsq . n is_measurable_on E0 by MESFUNC6:def_1; then (Fsq . n) | E0 is_measurable_on E0 by A15, MESFUNC6:76; then A16: Fsq2 . n is_measurable_on E0 by MESFUN9C:def_1; A17: dom (Fsq2 . n) = E0 by A13; ( dom ((abs (Fsq . n)) to_power k) = dom (abs (Fsq . n)) & dom ((abs (Fsq2 . n)) to_power k) = dom (abs (Fsq2 . n)) ) by MESFUN6C:def_4; then A18: ( dom ((abs (Fsq . n)) to_power k) = dom (Fsq . n) & dom ((abs (Fsq2 . n)) to_power k) = dom (Fsq2 . n) ) by VALUED_1:def_11; for x being set st x in dom ((abs (Fsq2 . n)) to_power k) holds ((abs (Fsq2 . n)) to_power k) . x = ((abs (Fsq . n)) to_power k) . x proof let x be set ; ::_thesis: ( x in dom ((abs (Fsq2 . n)) to_power k) implies ((abs (Fsq2 . n)) to_power k) . x = ((abs (Fsq . n)) to_power k) . x ) assume A19: x in dom ((abs (Fsq2 . n)) to_power k) ; ::_thesis: ((abs (Fsq2 . n)) to_power k) . x = ((abs (Fsq . n)) to_power k) . x then reconsider x0 = x as Element of X ; A20: x in dom ((abs (Fsq . n)) to_power k) by A17, A18, A15, A19, XBOOLE_0:def_4; thus ((abs (Fsq2 . n)) to_power k) . x = ((abs (Fsq2 . n)) . x0) to_power k by A19, MESFUN6C:def_4 .= (abs ((Fsq2 . n) . x0)) to_power k by VALUED_1:18 .= (abs (((Fsq . n) | E0) . x0)) to_power k by MESFUN9C:def_1 .= (abs ((Fsq . n) . x0)) to_power k by A17, A18, A19, FUNCT_1:49 .= ((abs (Fsq . n)) . x0) to_power k by VALUED_1:18 .= ((abs (Fsq . n)) to_power k) . x by A20, MESFUN6C:def_4 ; ::_thesis: verum end; then ((abs (Fsq . n)) to_power k) | E0 = (abs (Fsq2 . n)) to_power k by A13, A15, A18, FUNCT_1:46; then (abs (Fsq2 . n)) to_power k is_integrable_on M by A14, MESFUNC6:91; hence A21: Fsq2 . n in Lp_Functions (M,k) by A16, A17, A12; ::_thesis: ( Fsq2 . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq2 . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq2 . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) A22: ( Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) ) by A1; reconsider EB = E0 ` as Element of S by MEASURE1:34; (Fsq2 . n) | (EB `) = Fsq2 . n by A17, RELAT_1:68; then (Fsq2 . n) | (EB `) = (Fsq . n) | (EB `) by MESFUN9C:def_1; then A23: Fsq2 . n a.e.= Fsq . n,M by A12, LPSPACE1:def_10; hence Fsq2 . n in Sq . n by A22, A21, Th36; ::_thesis: ( Sq . n = a.e-eq-class_Lp ((Fsq2 . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq2 . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) a.e-eq-class_Lp ((Fsq2 . n),M,k) = a.e-eq-class_Lp ((Fsq . n),M,k) by Th42, A23; hence Sq . n = a.e-eq-class_Lp ((Fsq2 . n),M,k) by A1; ::_thesis: ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq2 . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) hence ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq2 . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) by Th53, Th38, A21; ::_thesis: verum end; end; Lm7: for X being RealNormSpace for Sq being sequence of X for Sq0 being Point of X for R1 being Real_Sequence for N being V167() sequence of NAT st Sq is Cauchy_sequence_by_Norm & ( for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| ) & R1 is convergent & lim R1 = 0 holds ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) proof let X be RealNormSpace; ::_thesis: for Sq being sequence of X for Sq0 being Point of X for R1 being Real_Sequence for N being V167() sequence of NAT st Sq is Cauchy_sequence_by_Norm & ( for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| ) & R1 is convergent & lim R1 = 0 holds ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) let Sq be sequence of X; ::_thesis: for Sq0 being Point of X for R1 being Real_Sequence for N being V167() sequence of NAT st Sq is Cauchy_sequence_by_Norm & ( for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| ) & R1 is convergent & lim R1 = 0 holds ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) let Sq0 be Point of X; ::_thesis: for R1 being Real_Sequence for N being V167() sequence of NAT st Sq is Cauchy_sequence_by_Norm & ( for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| ) & R1 is convergent & lim R1 = 0 holds ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) let R1 be Real_Sequence; ::_thesis: for N being V167() sequence of NAT st Sq is Cauchy_sequence_by_Norm & ( for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| ) & R1 is convergent & lim R1 = 0 holds ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) let N be V167() sequence of NAT; ::_thesis: ( Sq is Cauchy_sequence_by_Norm & ( for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| ) & R1 is convergent & lim R1 = 0 implies ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) ) assume that A1: Sq is Cauchy_sequence_by_Norm and A2: for i being Nat holds R1 . i = ||.(Sq0 - (Sq . (N . i))).|| and A3: ( R1 is convergent & lim R1 = 0 ) ; ::_thesis: ( Sq is convergent & lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) A4: now__::_thesis:_for_p_being_Real_st_0_<_p_holds_ ex_n3_being_Element_of_NAT_st_ for_n_being_Element_of_NAT_st_n3_<=_n_holds_ ||.((Sq_._n)_-_Sq0).||_<_p let p be Real; ::_thesis: ( 0 < p implies ex n3 being Element of NAT st for n being Element of NAT st n3 <= n holds ||.((Sq . n) - Sq0).|| < p ) assume A5: 0 < p ; ::_thesis: ex n3 being Element of NAT st for n being Element of NAT st n3 <= n holds ||.((Sq . n) - Sq0).|| < p then consider n2 being Element of NAT such that A6: for m, n being Element of NAT st n2 <= m & n2 <= n holds ||.((Sq . m) - (Sq . n)).|| < p / 2 by A1, RSSPACE3:8; consider n1 being Element of NAT such that A7: for l being Element of NAT st n1 <= l holds abs ((R1 . l) - 0) < p / 2 by A3, A5, SEQ_2:def_7; reconsider n3 = max (n1,n2) as Element of NAT ; take n3 = n3; ::_thesis: for n being Element of NAT st n3 <= n holds ||.((Sq . n) - Sq0).|| < p thus for n being Element of NAT st n3 <= n holds ||.((Sq . n) - Sq0).|| < p ::_thesis: verum proof let n be Element of NAT ; ::_thesis: ( n3 <= n implies ||.((Sq . n) - Sq0).|| < p ) assume A8: n3 <= n ; ::_thesis: ||.((Sq . n) - Sq0).|| < p n1 <= n3 by XXREAL_0:25; then n1 <= n by A8, XXREAL_0:2; then abs ((R1 . n) - 0) < p / 2 by A7; then A9: abs ||.(Sq0 - (Sq . (N . n))).|| < p / 2 by A2; A10: ||.(Sq0 - (Sq . (N . n))).|| < p / 2 by A9, ABSVALUE:def_1; n <= N . n by SEQM_3:14; then A11: n3 <= N . n by A8, XXREAL_0:2; n2 <= n3 by XXREAL_0:25; then ( n2 <= N . n & n2 <= n ) by A8, A11, XXREAL_0:2; then ||.((Sq . (N . n)) - (Sq . n)).|| < p / 2 by A6; then A12: ||.(Sq0 - (Sq . (N . n))).|| + ||.((Sq . (N . n)) - (Sq . n)).|| < (p / 2) + (p / 2) by A10, XREAL_1:8; A13: ||.((Sq . n) - Sq0).|| = ||.(Sq0 - (Sq . n)).|| by NORMSP_1:7 .= ||.((Sq0 - (Sq . (N . n))) + ((Sq . (N . n)) - (Sq . n))).|| by LOPBAN_3:3 ; ||.((Sq0 - (Sq . (N . n))) + ((Sq . (N . n)) - (Sq . n))).|| <= ||.(Sq0 - (Sq . (N . n))).|| + ||.((Sq . (N . n)) - (Sq . n)).|| by NORMSP_1:def_1; hence ||.((Sq . n) - Sq0).|| < p by A13, A12, XXREAL_0:2; ::_thesis: verum end; end; hence A14: Sq is convergent by NORMSP_1:def_6; ::_thesis: ( lim Sq = Sq0 & ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) hence lim Sq = Sq0 by A4, NORMSP_1:def_7; ::_thesis: ( ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) hence ( ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) by A14, NORMSP_1:24; ::_thesis: verum end; theorem :: LPSPACE2:64 for X being RealNormSpace for Sq being sequence of X for Sq0 being Point of X st ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 holds ( Sq is convergent & lim Sq = Sq0 ) proof let X be RealNormSpace; ::_thesis: for Sq being sequence of X for Sq0 being Point of X st ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 holds ( Sq is convergent & lim Sq = Sq0 ) let Sq be sequence of X; ::_thesis: for Sq0 being Point of X st ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 holds ( Sq is convergent & lim Sq = Sq0 ) let Sq0 be Point of X; ::_thesis: ( ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 implies ( Sq is convergent & lim Sq = Sq0 ) ) assume A1: ( ||.(Sq - Sq0).|| is convergent & lim ||.(Sq - Sq0).|| = 0 ) ; ::_thesis: ( Sq is convergent & lim Sq = Sq0 ) A2: for p being Real st 0 < p holds ex n being Element of NAT st for m being Element of NAT st n <= m holds ||.((Sq . m) - Sq0).|| < p proof let p be Real; ::_thesis: ( 0 < p implies ex n being Element of NAT st for m being Element of NAT st n <= m holds ||.((Sq . m) - Sq0).|| < p ) assume 0 < p ; ::_thesis: ex n being Element of NAT st for m being Element of NAT st n <= m holds ||.((Sq . m) - Sq0).|| < p then consider n being Element of NAT such that A3: for m being Element of NAT st n <= m holds abs ((||.(Sq - Sq0).|| . m) - 0) < p by A1, SEQ_2:def_7; take n ; ::_thesis: for m being Element of NAT st n <= m holds ||.((Sq . m) - Sq0).|| < p hereby ::_thesis: verum let m be Element of NAT ; ::_thesis: ( n <= m implies ||.((Sq . m) - Sq0).|| < p ) assume n <= m ; ::_thesis: ||.((Sq . m) - Sq0).|| < p then abs ((||.(Sq - Sq0).|| . m) - 0) < p by A3; then abs ||.((Sq - Sq0) . m).|| < p by NORMSP_0:def_4; then abs ||.((Sq . m) - Sq0).|| < p by NORMSP_1:def_4; hence ||.((Sq . m) - Sq0).|| < p by ABSVALUE:def_1; ::_thesis: verum end; end; hence Sq is convergent by NORMSP_1:def_6; ::_thesis: lim Sq = Sq0 hence lim Sq = Sq0 by A2, NORMSP_1:def_7; ::_thesis: verum end; theorem Th65: :: LPSPACE2:65 for X being RealNormSpace for Sq being sequence of X st Sq is Cauchy_sequence_by_Norm holds ex N being V167() sequence of NAT st for i, j being Element of NAT st j >= N . i holds ||.((Sq . j) - (Sq . (N . i))).|| < 2 to_power (- i) proof let X be RealNormSpace; ::_thesis: for Sq being sequence of X st Sq is Cauchy_sequence_by_Norm holds ex N being V167() sequence of NAT st for i, j being Element of NAT st j >= N . i holds ||.((Sq . j) - (Sq . (N . i))).|| < 2 to_power (- i) let Sq be sequence of X; ::_thesis: ( Sq is Cauchy_sequence_by_Norm implies ex N being V167() sequence of NAT st for i, j being Element of NAT st j >= N . i holds ||.((Sq . j) - (Sq . (N . i))).|| < 2 to_power (- i) ) assume A1: Sq is Cauchy_sequence_by_Norm ; ::_thesis: ex N being V167() sequence of NAT st for i, j being Element of NAT st j >= N . i holds ||.((Sq . j) - (Sq . (N . i))).|| < 2 to_power (- i) 1 = 2 to_power (- 0) by POWER:24; then consider N0 being Element of NAT such that A2: for j, i being Element of NAT st j >= N0 & i >= N0 holds ||.((Sq . j) - (Sq . i)).|| < 2 to_power (- 0) by A1, RSSPACE3:8; defpred S1[ set , set , set ] means ex n, x, y being Element of NAT st ( n = $1 & x = $2 & y = $3 & ( ( for j being Element of NAT st j >= x holds ||.((Sq . j) - (Sq . x)).|| < 2 to_power (- n) ) implies ( x < y & ( for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ) ) ) ); A3: for n, x being Element of NAT ex y being Element of NAT st S1[n,x,y] proof let n, x be Element of NAT ; ::_thesis: ex y being Element of NAT st S1[n,x,y] now__::_thesis:_(_(_for_j_being_Element_of_NAT_st_j_>=_x_holds_ ||.((Sq_._j)_-_(Sq_._x)).||_<_2_to_power_(-_n)_)_implies_ex_y_being_Element_of_NAT_st_ (_x_<_y_&_(_for_j_being_Element_of_NAT_st_j_>=_y_holds_ ||.((Sq_._j)_-_(Sq_._y)).||_<_2_to_power_(-_(n_+_1))_)_)_) assume for j being Element of NAT st j >= x holds ||.((Sq . j) - (Sq . x)).|| < 2 to_power (- n) ; ::_thesis: ex y being Element of NAT st ( x < y & ( for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ) ) 0 < 2 to_power (- (n + 1)) by POWER:34; then consider N2 being Element of NAT such that A4: for j, i being Element of NAT st j >= N2 & i >= N2 holds ||.((Sq . j) - (Sq . i)).|| < 2 to_power (- (n + 1)) by A1, RSSPACE3:8; set y = (max (x,N2)) + 1; take y = (max (x,N2)) + 1; ::_thesis: ( x < y & ( for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ) ) x <= max (x,N2) by XXREAL_0:25; hence x < y by NAT_1:13; ::_thesis: for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) N2 <= max (x,N2) by XXREAL_0:25; then A5: N2 < y by NAT_1:13; thus for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ::_thesis: verum proof let j be Element of NAT ; ::_thesis: ( j >= y implies ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ) assume j >= y ; ::_thesis: ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) then ( j >= N2 & y >= N2 ) by A5, XXREAL_0:2; hence ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) by A4; ::_thesis: verum end; end; hence ex y being Element of NAT st S1[n,x,y] ; ::_thesis: verum end; consider f being Function of NAT,NAT such that A6: ( f . 0 = N0 & ( for n being Element of NAT holds S1[n,f . n,f . (n + 1)] ) ) from RECDEF_1:sch_2(A3); defpred S2[ Element of NAT ] means for j being Element of NAT st j >= f . $1 holds ||.((Sq . j) - (Sq . (f . $1))).|| < 2 to_power (- $1); A7: S2[ 0 ] by A2, A6; A8: now__::_thesis:_for_i_being_Element_of_NAT_st_S2[i]_holds_ S2[i_+_1] let i be Element of NAT ; ::_thesis: ( S2[i] implies S2[i + 1] ) assume A9: S2[i] ; ::_thesis: S2[i + 1] ex n, x, y being Element of NAT st ( n = i & x = f . i & y = f . (i + 1) & ( ( for j being Element of NAT st j >= x holds ||.((Sq . j) - (Sq . x)).|| < 2 to_power (- n) ) implies ( x < y & ( for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ) ) ) ) by A6; hence S2[i + 1] by A9; ::_thesis: verum end; A10: for i being Element of NAT holds S2[i] from NAT_1:sch_1(A7, A8); A11: f is Real_Sequence by FUNCT_2:7; now__::_thesis:_for_i_being_Element_of_NAT_holds_f_._i_<_f_._(i_+_1) let i be Element of NAT ; ::_thesis: f . i < f . (i + 1) ex n, x, y being Element of NAT st ( n = i & x = f . i & y = f . (i + 1) & ( ( for j being Element of NAT st j >= x holds ||.((Sq . j) - (Sq . x)).|| < 2 to_power (- n) ) implies ( x < y & ( for j being Element of NAT st j >= y holds ||.((Sq . j) - (Sq . y)).|| < 2 to_power (- (n + 1)) ) ) ) ) by A6; hence f . i < f . (i + 1) by A10; ::_thesis: verum end; then f is V167() by A11, SEQM_3:def_6; hence ex N being V167() sequence of NAT st for i, j being Element of NAT st j >= N . i holds ||.((Sq . j) - (Sq . (N . i))).|| < 2 to_power (- i) by A10; ::_thesis: verum end; theorem Th66: :: LPSPACE2:66 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m in Lp_Functions (M,k) ) holds for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being positive Real for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m in Lp_Functions (M,k) ) holds for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being positive Real for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m in Lp_Functions (M,k) ) holds for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) let M be sigma_Measure of S; ::_thesis: for k being positive Real for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m in Lp_Functions (M,k) ) holds for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) let k be positive Real; ::_thesis: for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m in Lp_Functions (M,k) ) holds for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) let F be Functional_Sequence of X,REAL; ::_thesis: ( ( for m being Nat holds F . m in Lp_Functions (M,k) ) implies for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) ) assume A1: for m being Nat holds F . m in Lp_Functions (M,k) ; ::_thesis: for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) defpred S1[ Nat] means (Partial_Sums F) . $1 in Lp_Functions (M,k); (Partial_Sums F) . 0 = F . 0 by MESFUN9C:def_2; then A2: S1[ 0 ] by A1; A3: now__::_thesis:_for_j_being_Nat_st_S1[j]_holds_ S1[j_+_1] let j be Nat; ::_thesis: ( S1[j] implies S1[j + 1] ) assume S1[j] ; ::_thesis: S1[j + 1] then A4: ( (Partial_Sums F) . j in Lp_Functions (M,k) & F . (j + 1) in Lp_Functions (M,k) ) by A1; (Partial_Sums F) . (j + 1) = ((Partial_Sums F) . j) + (F . (j + 1)) by MESFUN9C:def_2; hence S1[j + 1] by A4, Th25; ::_thesis: verum end; for j being Nat holds S1[j] from NAT_1:sch_2(A2, A3); hence for m being Nat holds (Partial_Sums F) . m in Lp_Functions (M,k) ; ::_thesis: verum end; theorem Th67: :: LPSPACE2:67 for X being non empty set for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m is nonnegative ) holds for m being Nat holds (Partial_Sums F) . m is nonnegative proof let X be non empty set ; ::_thesis: for F being Functional_Sequence of X,REAL st ( for m being Nat holds F . m is nonnegative ) holds for m being Nat holds (Partial_Sums F) . m is nonnegative let F be Functional_Sequence of X,REAL; ::_thesis: ( ( for m being Nat holds F . m is nonnegative ) implies for m being Nat holds (Partial_Sums F) . m is nonnegative ) assume A1: for m being Nat holds F . m is nonnegative ; ::_thesis: for m being Nat holds (Partial_Sums F) . m is nonnegative defpred S1[ Nat] means (Partial_Sums F) . $1 is nonnegative ; (Partial_Sums F) . 0 = F . 0 by MESFUN9C:def_2; then A2: S1[ 0 ] by A1; A3: now__::_thesis:_for_k_being_Nat_st_S1[k]_holds_ S1[k_+_1] let k be Nat; ::_thesis: ( S1[k] implies S1[k + 1] ) assume S1[k] ; ::_thesis: S1[k + 1] then A4: ( (Partial_Sums F) . k is nonnegative & F . (k + 1) is nonnegative ) by A1; (Partial_Sums F) . (k + 1) = ((Partial_Sums F) . k) + (F . (k + 1)) by MESFUN9C:def_2; hence S1[k + 1] by A4, MESFUNC6:56; ::_thesis: verum end; for k being Nat holds S1[k] from NAT_1:sch_2(A2, A3); hence for m being Nat holds (Partial_Sums F) . m is nonnegative ; ::_thesis: verum end; theorem Th68: :: LPSPACE2:68 for X being non empty set for F being Functional_Sequence of X,REAL for x being Element of X for n, m being Nat st F is with_the_same_dom & x in dom (F . 0) & ( for k being Nat holds F . k is nonnegative ) & n <= m holds ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x proof let X be non empty set ; ::_thesis: for F being Functional_Sequence of X,REAL for x being Element of X for n, m being Nat st F is with_the_same_dom & x in dom (F . 0) & ( for k being Nat holds F . k is nonnegative ) & n <= m holds ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x let F be Functional_Sequence of X,REAL; ::_thesis: for x being Element of X for n, m being Nat st F is with_the_same_dom & x in dom (F . 0) & ( for k being Nat holds F . k is nonnegative ) & n <= m holds ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x let x be Element of X; ::_thesis: for n, m being Nat st F is with_the_same_dom & x in dom (F . 0) & ( for k being Nat holds F . k is nonnegative ) & n <= m holds ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x let n, m be Nat; ::_thesis: ( F is with_the_same_dom & x in dom (F . 0) & ( for k being Nat holds F . k is nonnegative ) & n <= m implies ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x ) assume A1: F is with_the_same_dom ; ::_thesis: ( not x in dom (F . 0) or ex k being Nat st not F . k is nonnegative or not n <= m or ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x ) assume A2: x in dom (F . 0) ; ::_thesis: ( ex k being Nat st not F . k is nonnegative or not n <= m or ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x ) assume A3: for m being Nat holds F . m is nonnegative ; ::_thesis: ( not n <= m or ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x ) assume A4: n <= m ; ::_thesis: ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x set PF = Partial_Sums F; defpred S1[ Nat] means ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . $1) . x; A5: for k being Nat holds ((Partial_Sums F) . k) . x <= ((Partial_Sums F) . (k + 1)) . x proof let k be Nat; ::_thesis: ((Partial_Sums F) . k) . x <= ((Partial_Sums F) . (k + 1)) . x A6: (Partial_Sums F) . (k + 1) = ((Partial_Sums F) . k) + (F . (k + 1)) by MESFUN9C:def_2; A7: dom ((Partial_Sums F) . (k + 1)) = dom (F . 0) by A1, MESFUN9C:11; ( F . (k + 1) is nonnegative & (Partial_Sums F) . k is nonnegative ) by A3, Th67; then ( 0 <= (F . (k + 1)) . x & 0 <= ((Partial_Sums F) . k) . x ) by MESFUNC6:51; then (((Partial_Sums F) . k) . x) + 0 <= (((Partial_Sums F) . k) . x) + ((F . (k + 1)) . x) by XREAL_1:7; hence ((Partial_Sums F) . k) . x <= ((Partial_Sums F) . (k + 1)) . x by A7, A2, A6, VALUED_1:def_1; ::_thesis: verum end; A8: for k being Nat st k >= n & ( for l being Nat st l >= n & l < k holds S1[l] ) holds S1[k] proof let k be Nat; ::_thesis: ( k >= n & ( for l being Nat st l >= n & l < k holds S1[l] ) implies S1[k] ) assume A9: ( k >= n & ( for l being Nat st l >= n & l < k holds S1[l] ) ) ; ::_thesis: S1[k] now__::_thesis:_(_k_>_n_implies_S1[k]_) assume k > n ; ::_thesis: S1[k] then k >= n + 1 by NAT_1:13; then A10: ( k = n + 1 or k > n + 1 ) by XXREAL_0:1; now__::_thesis:_(_k_>_n_+_1_implies_S1[k]_) assume A11: k > n + 1 ; ::_thesis: S1[k] then reconsider l = k - 1 as Element of NAT by NAT_1:20; k < k + 1 by NAT_1:13; then ( k > l & l >= n ) by A11, XREAL_1:19; then A12: ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . l) . x by A9; k = l + 1 ; then ((Partial_Sums F) . l) . x <= ((Partial_Sums F) . k) . x by A5; hence S1[k] by A12, XXREAL_0:2; ::_thesis: verum end; hence S1[k] by A10, A5; ::_thesis: verum end; hence S1[k] by A9, XXREAL_0:1; ::_thesis: verum end; for k being Nat st k >= n holds S1[k] from NAT_1:sch_9(A8); hence ((Partial_Sums F) . n) . x <= ((Partial_Sums F) . m) . x by A4; ::_thesis: verum end; theorem Th69: :: LPSPACE2:69 for X being non empty set for F being Functional_Sequence of X,REAL st F is with_the_same_dom holds abs F is with_the_same_dom proof let X be non empty set ; ::_thesis: for F being Functional_Sequence of X,REAL st F is with_the_same_dom holds abs F is with_the_same_dom let F be Functional_Sequence of X,REAL; ::_thesis: ( F is with_the_same_dom implies abs F is with_the_same_dom ) assume A1: F is with_the_same_dom ; ::_thesis: abs F is with_the_same_dom for n, m being Nat holds dom ((abs F) . n) = dom ((abs F) . m) proof let n, m be Nat; ::_thesis: dom ((abs F) . n) = dom ((abs F) . m) ( (abs F) . n = abs (F . n) & (abs F) . m = abs (F . m) ) by SEQFUNC:def_4; then ( dom ((abs F) . n) = dom (F . n) & dom ((abs F) . m) = dom (F . m) ) by VALUED_1:def_11; hence dom ((abs F) . n) = dom ((abs F) . m) by A1, MESFUNC8:def_2; ::_thesis: verum end; hence abs F is with_the_same_dom by MESFUNC8:def_2; ::_thesis: verum end; theorem Th70: :: LPSPACE2:70 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for k being geq_than_1 Real for Sq being sequence of (Lp-Space (M,k)) st Sq is Cauchy_sequence_by_Norm holds Sq is convergent proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for k being geq_than_1 Real for Sq being sequence of (Lp-Space (M,k)) st Sq is Cauchy_sequence_by_Norm holds Sq is convergent let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for k being geq_than_1 Real for Sq being sequence of (Lp-Space (M,k)) st Sq is Cauchy_sequence_by_Norm holds Sq is convergent let M be sigma_Measure of S; ::_thesis: for k being geq_than_1 Real for Sq being sequence of (Lp-Space (M,k)) st Sq is Cauchy_sequence_by_Norm holds Sq is convergent let k be geq_than_1 Real; ::_thesis: for Sq being sequence of (Lp-Space (M,k)) st Sq is Cauchy_sequence_by_Norm holds Sq is convergent let Sq be sequence of (Lp-Space (M,k)); ::_thesis: ( Sq is Cauchy_sequence_by_Norm implies Sq is convergent ) A1: 1 <= k by Def1; assume A2: Sq is Cauchy_sequence_by_Norm ; ::_thesis: Sq is convergent consider Fsq being with_the_same_dom Functional_Sequence of X,REAL such that A3: for n being Element of NAT holds ( Fsq . n in Lp_Functions (M,k) & Fsq . n in Sq . n & Sq . n = a.e-eq-class_Lp ((Fsq . n),M,k) & ex r being Real st ( 0 <= r & r = Integral (M,((abs (Fsq . n)) to_power k)) & ||.(Sq . n).|| = r to_power (1 / k) ) ) by Th63; Fsq . 0 in Lp_Functions (M,k) by A3; then A4: ex D being Element of S st ( M . (D `) = 0 & dom (Fsq . 0) = D & Fsq . 0 is_measurable_on D ) by Th35; then reconsider E = dom (Fsq . 0) as Element of S ; consider N being V167() sequence of NAT such that A5: for i, j being Element of NAT st j >= N . i holds ||.((Sq . j) - (Sq . (N . i))).|| < 2 to_power (- i) by Th65, A2; deffunc H1( Nat) -> Element of bool [:X,REAL:] = Fsq . (N . $1); consider F1 being Functional_Sequence of X,REAL such that A6: for n being Nat holds F1 . n = H1(n) from SEQFUNC:sch_1(); A7: for n being Nat holds ( dom (F1 . n) = E & F1 . n in Lp_Functions (M,k) & F1 . n is_measurable_on E & abs (F1 . n) in Lp_Functions (M,k) ) proof let n be Nat; ::_thesis: ( dom (F1 . n) = E & F1 . n in Lp_Functions (M,k) & F1 . n is_measurable_on E & abs (F1 . n) in Lp_Functions (M,k) ) A8: F1 . n = Fsq . (N . n) by A6; hence A9: ( dom (F1 . n) = E & F1 . n in Lp_Functions (M,k) ) by A3, MESFUNC8:def_2; ::_thesis: ( F1 . n is_measurable_on E & abs (F1 . n) in Lp_Functions (M,k) ) then ex F being PartFunc of X,REAL st ( F1 . n = F & ex ND being Element of S st ( M . (ND `) = 0 & dom F = ND & F is_measurable_on ND & (abs F) to_power k is_integrable_on M ) ) ; hence F1 . n is_measurable_on E by A8, MESFUNC8:def_2; ::_thesis: abs (F1 . n) in Lp_Functions (M,k) thus abs (F1 . n) in Lp_Functions (M,k) by A9, Th28; ::_thesis: verum end; for n, m being Nat holds dom (F1 . n) = dom (F1 . m) proof let n, m be Nat; ::_thesis: dom (F1 . n) = dom (F1 . m) ( dom (F1 . n) = E & dom (F1 . m) = E ) by A7; hence dom (F1 . n) = dom (F1 . m) ; ::_thesis: verum end; then reconsider F1 = F1 as with_the_same_dom Functional_Sequence of X,REAL by MESFUNC8:def_2; deffunc H2( Nat) -> Element of bool [:X,REAL:] = (F1 . ($1 + 1)) - (F1 . $1); consider FMF being Functional_Sequence of X,REAL such that A10: for n being Nat holds FMF . n = H2(n) from SEQFUNC:sch_1(); A11: for n being Nat holds ( dom (FMF . n) = E & FMF . n in Lp_Functions (M,k) ) proof let n be Nat; ::_thesis: ( dom (FMF . n) = E & FMF . n in Lp_Functions (M,k) ) A12: ( dom (F1 . n) = E & dom (F1 . (n + 1)) = E ) by A7; FMF . n = (F1 . (n + 1)) - (F1 . n) by A10; then dom (FMF . n) = (dom (F1 . (n + 1))) /\ (dom (F1 . n)) by VALUED_1:12; hence dom (FMF . n) = E by A12; ::_thesis: FMF . n in Lp_Functions (M,k) ( Fsq . (N . (n + 1)) in Lp_Functions (M,k) & Fsq . (N . n) in Lp_Functions (M,k) ) by A3; then ( F1 . (n + 1) in Lp_Functions (M,k) & F1 . n in Lp_Functions (M,k) ) by A6; then (F1 . (n + 1)) - (F1 . n) in Lp_Functions (M,k) by Th27; hence FMF . n in Lp_Functions (M,k) by A10; ::_thesis: verum end; for n, m being Nat holds dom (FMF . n) = dom (FMF . m) proof let n, m be Nat; ::_thesis: dom (FMF . n) = dom (FMF . m) ( dom (FMF . n) = E & dom (FMF . m) = E ) by A11; hence dom (FMF . n) = dom (FMF . m) ; ::_thesis: verum end; then reconsider FMF = FMF as with_the_same_dom Functional_Sequence of X,REAL by MESFUNC8:def_2; set AbsFMF = abs FMF; A13: for n being Nat holds ( (abs FMF) . n is nonnegative & dom ((abs FMF) . n) = E & abs ((abs FMF) . n) = (abs FMF) . n & (abs FMF) . n in Lp_Functions (M,k) & (abs FMF) . n is_measurable_on E ) proof let n be Nat; ::_thesis: ( (abs FMF) . n is nonnegative & dom ((abs FMF) . n) = E & abs ((abs FMF) . n) = (abs FMF) . n & (abs FMF) . n in Lp_Functions (M,k) & (abs FMF) . n is_measurable_on E ) A14: (abs FMF) . n = abs (FMF . n) by SEQFUNC:def_4; hence (abs FMF) . n is nonnegative ; ::_thesis: ( dom ((abs FMF) . n) = E & abs ((abs FMF) . n) = (abs FMF) . n & (abs FMF) . n in Lp_Functions (M,k) & (abs FMF) . n is_measurable_on E ) A15: ( dom (FMF . n) = E & FMF . n in Lp_Functions (M,k) ) by A11; hence ( dom ((abs FMF) . n) = E & abs ((abs FMF) . n) = (abs FMF) . n ) by A14, VALUED_1:def_11; ::_thesis: ( (abs FMF) . n in Lp_Functions (M,k) & (abs FMF) . n is_measurable_on E ) thus (abs FMF) . n in Lp_Functions (M,k) by A11, A14, Th28; ::_thesis: (abs FMF) . n is_measurable_on E then ex D being Element of S st ( M . (D `) = 0 & dom ((abs FMF) . n) = D & (abs FMF) . n is_measurable_on D ) by Th35; hence (abs FMF) . n is_measurable_on E by A15, A14, VALUED_1:def_11; ::_thesis: verum end; reconsider AbsFMF = abs FMF as with_the_same_dom Functional_Sequence of X,REAL by Th69; deffunc H3( Nat) -> Element of bool [:X,REAL:] = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . $1); consider G being Functional_Sequence of X,REAL such that A16: for n being Nat holds G . n = H3(n) from SEQFUNC:sch_1(); A17: for n being Nat holds ( dom (G . n) = E & G . n in Lp_Functions (M,k) & G . n is nonnegative & G . n is_measurable_on E & abs (G . n) = G . n ) proof let n be Nat; ::_thesis: ( dom (G . n) = E & G . n in Lp_Functions (M,k) & G . n is nonnegative & G . n is_measurable_on E & abs (G . n) = G . n ) A18: G . n = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . n) by A16; then A19: dom (G . n) = (dom (abs (F1 . 0))) /\ (dom ((Partial_Sums AbsFMF) . n)) by VALUED_1:def_1 .= (dom (F1 . 0)) /\ (dom ((Partial_Sums AbsFMF) . n)) by VALUED_1:def_11 .= (dom (F1 . 0)) /\ (dom (AbsFMF . 0)) by MESFUN9C:11 ; A20: ( (Partial_Sums AbsFMF) . n in Lp_Functions (M,k) & (Partial_Sums AbsFMF) . n is nonnegative & (Partial_Sums AbsFMF) . n is_measurable_on E ) by A13, Th66, Th67, MESFUN9C:16; A21: dom (AbsFMF . 0) = E by A13; A22: ( F1 . 0 in Lp_Functions (M,k) & dom (F1 . 0) = E & F1 . 0 is_measurable_on E ) by A7; then ( abs (F1 . 0) in Lp_Functions (M,k) & abs (F1 . 0) is nonnegative & abs (F1 . 0) is_measurable_on E ) by Th28, MESFUNC6:48; hence ( dom (G . n) = E & G . n in Lp_Functions (M,k) & G . n is nonnegative & G . n is_measurable_on E & abs (G . n) = G . n ) by A19, A22, A21, A18, A20, Th14, Th25, MESFUNC6:26, MESFUNC6:56; ::_thesis: verum end; deffunc H4( Nat) -> Element of bool [:X,REAL:] = (G . $1) to_power k; consider Gp being Functional_Sequence of X,REAL such that A23: for n being Nat holds Gp . n = H4(n) from SEQFUNC:sch_1(); A24: for n being Nat holds ( (G . n) to_power k is nonnegative & (G . n) to_power k is_measurable_on E ) proof let n be Nat; ::_thesis: ( (G . n) to_power k is nonnegative & (G . n) to_power k is_measurable_on E ) A25: G . n is nonnegative by A17; hence (G . n) to_power k is nonnegative ; ::_thesis: (G . n) to_power k is_measurable_on E ( G . n is_measurable_on E & dom (G . n) = E ) by A17; hence (G . n) to_power k is_measurable_on E by A25, MESFUN6C:29; ::_thesis: verum end; reconsider ExtGp = R_EAL Gp as Functional_Sequence of X,ExtREAL ; A26: for n being Nat holds ( dom (ExtGp . n) = E & ExtGp . n is_measurable_on E & ExtGp . n is nonnegative ) proof let n be Nat; ::_thesis: ( dom (ExtGp . n) = E & ExtGp . n is_measurable_on E & ExtGp . n is nonnegative ) ExtGp . n = R_EAL ((G . n) to_power k) by A23; then dom (ExtGp . n) = dom (G . n) by MESFUN6C:def_4; hence dom (ExtGp . n) = E by A17; ::_thesis: ( ExtGp . n is_measurable_on E & ExtGp . n is nonnegative ) (G . n) to_power k is_measurable_on E by A24; then R_EAL ((G . n) to_power k) is_measurable_on E by MESFUNC6:def_1; hence ExtGp . n is_measurable_on E by A23; ::_thesis: ExtGp . n is nonnegative (G . n) to_power k is nonnegative by A24; hence ExtGp . n is nonnegative by A23; ::_thesis: verum end; then A27: ( dom (ExtGp . 0) = E & ExtGp . 0 is nonnegative ) ; for n, m being Nat holds dom (ExtGp . n) = dom (ExtGp . m) proof let n, m be Nat; ::_thesis: dom (ExtGp . n) = dom (ExtGp . m) ( dom (ExtGp . n) = E & dom (ExtGp . m) = E ) by A26; hence dom (ExtGp . n) = dom (ExtGp . m) ; ::_thesis: verum end; then reconsider ExtGp = ExtGp as with_the_same_dom Functional_Sequence of X,ExtREAL by MESFUNC8:def_2; A28: for n, m being Nat st n <= m holds for x being Element of X st x in E holds (ExtGp . n) . x <= (ExtGp . m) . x proof let n, m be Nat; ::_thesis: ( n <= m implies for x being Element of X st x in E holds (ExtGp . n) . x <= (ExtGp . m) . x ) assume A29: n <= m ; ::_thesis: for x being Element of X st x in E holds (ExtGp . n) . x <= (ExtGp . m) . x let x be Element of X; ::_thesis: ( x in E implies (ExtGp . n) . x <= (ExtGp . m) . x ) assume A30: x in E ; ::_thesis: (ExtGp . n) . x <= (ExtGp . m) . x then A31: ( x in dom (G . n) & x in dom (G . m) ) by A17; then ( x in dom ((G . n) to_power k) & x in dom ((G . m) to_power k) ) by MESFUN6C:def_4; then ( ((G . n) . x) to_power k = ((G . n) to_power k) . x & ((G . m) . x) to_power k = ((G . m) to_power k) . x ) by MESFUN6C:def_4; then A32: ( ((G . n) . x) to_power k = (ExtGp . n) . x & ((G . m) . x) to_power k = (ExtGp . m) . x ) by A23; dom (AbsFMF . 0) = E by A13; then ((Partial_Sums AbsFMF) . n) . x <= ((Partial_Sums AbsFMF) . m) . x by Th68, A29, A30, A13; then A33: ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . n) . x) <= ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . m) . x) by XREAL_1:6; ( G . m = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . m) & G . n = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . n) ) by A16; then A34: ( (G . m) . x = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . m) . x) & (G . n) . x = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . n) . x) ) by A31, VALUED_1:def_1; G . n is nonnegative by A17; then 0 <= (G . n) . x by MESFUNC6:51; hence (ExtGp . n) . x <= (ExtGp . m) . x by A32, A33, A34, HOLDER_1:3; ::_thesis: verum end; A35: for x being Element of X st x in E holds ExtGp # x is V169() proof let x be Element of X; ::_thesis: ( x in E implies ExtGp # x is V169() ) assume A36: x in E ; ::_thesis: ExtGp # x is V169() for n, m being Element of NAT st m <= n holds (ExtGp # x) . m <= (ExtGp # x) . n proof let n, m be Element of NAT ; ::_thesis: ( m <= n implies (ExtGp # x) . m <= (ExtGp # x) . n ) assume m <= n ; ::_thesis: (ExtGp # x) . m <= (ExtGp # x) . n then (ExtGp . m) . x <= (ExtGp . n) . x by A28, A36; then (ExtGp # x) . m <= (ExtGp . n) . x by MESFUNC5:def_13; hence (ExtGp # x) . m <= (ExtGp # x) . n by MESFUNC5:def_13; ::_thesis: verum end; hence ExtGp # x is V169() by RINFSUP2:7; ::_thesis: verum end; A37: for x being Element of X st x in E holds ExtGp # x is convergent proof let x be Element of X; ::_thesis: ( x in E implies ExtGp # x is convergent ) assume x in E ; ::_thesis: ExtGp # x is convergent then ExtGp # x is V169() by A35; hence ExtGp # x is convergent by RINFSUP2:37; ::_thesis: verum end; then consider I being ExtREAL_sequence such that A38: ( ( for n being Nat holds I . n = Integral (M,(ExtGp . n)) ) & I is convergent & Integral (M,(lim ExtGp)) = lim I ) by A27, A26, A28, MESFUNC9:52; now__::_thesis:_for_y_being_set_st_y_in_rng_I_holds_ y_in_REAL let y be set ; ::_thesis: ( y in rng I implies y in REAL ) assume y in rng I ; ::_thesis: y in REAL then consider x being Element of NAT such that A39: y = I . x by FUNCT_2:113; A40: y = Integral (M,(Gp . x)) by A39, A38; G . x = abs (G . x) by A17; then A41: Gp . x = (abs (G . x)) to_power k by A23; G . x in Lp_Functions (M,k) by A17; hence y in REAL by A40, A41, Th49; ::_thesis: verum end; then rng I c= REAL by TARSKI:def_3; then reconsider Ir = I as Function of NAT,REAL by FUNCT_2:6; deffunc H5( Nat) -> Element of ExtREAL = Integral (M,((AbsFMF . $1) to_power k)); A42: for x being Element of NAT holds H5(x) is Element of REAL proof let x be Element of NAT ; ::_thesis: H5(x) is Element of REAL AbsFMF . x in Lp_Functions (M,k) by A13; then Integral (M,((abs (AbsFMF . x)) to_power k)) in REAL by Th49; hence H5(x) is Element of REAL by A13; ::_thesis: verum end; consider KPAbsFMF being Function of NAT,REAL such that A43: for x being Element of NAT holds KPAbsFMF . x = H5(x) from FUNCT_2:sch_9(A42); deffunc H6( Nat) -> Element of REAL = (KPAbsFMF . $1) to_power (1 / k); A44: for x being Element of NAT holds H6(x) is Element of REAL ; consider PAbsFMF being Function of NAT,REAL such that A45: for x being Element of NAT holds PAbsFMF . x = H6(x) from FUNCT_2:sch_9(A44); F1 . 0 in Lp_Functions (M,k) by A7; then reconsider RF0 = Integral (M,((abs (F1 . 0)) to_power k)) as Element of REAL by Th49; deffunc H7( Element of NAT ) -> Element of REAL = (RF0 to_power (1 / k)) + ((Partial_Sums PAbsFMF) . $1); A46: for x being Element of NAT holds H7(x) is Element of REAL ; consider QAbsFMF being Function of NAT,REAL such that A47: for x being Element of NAT holds QAbsFMF . x = H7(x) from FUNCT_2:sch_9(A46); A48: for n being Element of NAT holds (Ir . n) to_power (1 / k) <= QAbsFMF . n proof defpred S1[ Nat] means (Ir . $1) to_power (1 / k) <= QAbsFMF . $1; A49: ( abs (F1 . 0) in Lp_Functions (M,k) & AbsFMF . 0 in Lp_Functions (M,k) ) by A13, A7; G . 0 = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . 0) by A16; then A50: G . 0 = (abs (F1 . 0)) + (AbsFMF . 0) by MESFUN9C:def_2; Ir . 0 = Integral (M,(Gp . 0)) by A38; then Ir . 0 = Integral (M,((G . 0) to_power k)) by A23; then A51: Ir . 0 = Integral (M,((abs ((abs (F1 . 0)) + (AbsFMF . 0))) to_power k)) by A17, A50; KPAbsFMF . 0 = Integral (M,((AbsFMF . 0) to_power k)) by A43; then A52: KPAbsFMF . 0 = Integral (M,((abs (AbsFMF . 0)) to_power k)) by A13; A53: RF0 = Integral (M,((abs (abs (F1 . 0))) to_power k)) ; QAbsFMF . 0 = (RF0 to_power (1 / k)) + ((Partial_Sums PAbsFMF) . 0) by A47; then QAbsFMF . 0 = (RF0 to_power (1 / k)) + (PAbsFMF . 0) by SERIES_1:def_1; then QAbsFMF . 0 = (RF0 to_power (1 / k)) + ((KPAbsFMF . 0) to_power (1 / k)) by A45; then A54: S1[ 0 ] by A1, A49, A51, A52, A53, Th61; A55: now__::_thesis:_for_n_being_Element_of_NAT_st_S1[n]_holds_ S1[n_+_1] let n be Element of NAT ; ::_thesis: ( S1[n] implies S1[n + 1] ) assume S1[n] ; ::_thesis: S1[n + 1] then A56: ((Ir . n) to_power (1 / k)) + (PAbsFMF . (n + 1)) <= (QAbsFMF . n) + (PAbsFMF . (n + 1)) by XREAL_1:6; G . (n + 1) = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . (n + 1)) by A16 .= (abs (F1 . 0)) + (((Partial_Sums AbsFMF) . n) + (AbsFMF . (n + 1))) by MESFUN9C:def_2 .= ((abs (F1 . 0)) + ((Partial_Sums AbsFMF) . n)) + (AbsFMF . (n + 1)) by RFUNCT_1:8 ; then A57: G . (n + 1) = (G . n) + (AbsFMF . (n + 1)) by A16; A58: ( AbsFMF . (n + 1) in Lp_Functions (M,k) & G . n in Lp_Functions (M,k) ) by A13, A17; KPAbsFMF . (n + 1) = Integral (M,((AbsFMF . (n + 1)) to_power k)) by A43; then A59: KPAbsFMF . (n + 1) = Integral (M,((abs (AbsFMF . (n + 1))) to_power k)) by A13; A60: PAbsFMF . (n + 1) = (KPAbsFMF . (n + 1)) to_power (1 / k) by A45; ( Ir . n = Integral (M,(Gp . n)) & Ir . (n + 1) = Integral (M,(Gp . (n + 1))) ) by A38; then ( Ir . n = Integral (M,((G . n) to_power k)) & Ir . (n + 1) = Integral (M,((G . (n + 1)) to_power k)) ) by A23; then ( Ir . n = Integral (M,((abs (G . n)) to_power k)) & Ir . (n + 1) = Integral (M,((abs ((G . n) + (AbsFMF . (n + 1)))) to_power k)) ) by A57, A17; then (Ir . (n + 1)) to_power (1 / k) <= ((Ir . n) to_power (1 / k)) + (PAbsFMF . (n + 1)) by A1, A58, A59, A60, Th61; then A61: (Ir . (n + 1)) to_power (1 / k) <= (QAbsFMF . n) + (PAbsFMF . (n + 1)) by A56, XXREAL_0:2; (QAbsFMF . n) + (PAbsFMF . (n + 1)) = ((RF0 to_power (1 / k)) + ((Partial_Sums PAbsFMF) . n)) + (PAbsFMF . (n + 1)) by A47 .= (RF0 to_power (1 / k)) + (((Partial_Sums PAbsFMF) . n) + (PAbsFMF . (n + 1))) .= (RF0 to_power (1 / k)) + ((Partial_Sums PAbsFMF) . (n + 1)) by SERIES_1:def_1 ; hence S1[n + 1] by A61, A47; ::_thesis: verum end; for n being Element of NAT holds S1[n] from NAT_1:sch_1(A54, A55); hence for n being Element of NAT holds (Ir . n) to_power (1 / k) <= QAbsFMF . n ; ::_thesis: verum end; A62: for n being Element of NAT holds PAbsFMF . n = ||.((Sq . (N . (n + 1))) - (Sq . (N . n))).|| proof let n be Element of NAT ; ::_thesis: PAbsFMF . n = ||.((Sq . (N . (n + 1))) - (Sq . (N . n))).|| set m = N . n; set m1 = N . (n + 1); A63: ( F1 . (n + 1) = Fsq . (N . (n + 1)) & F1 . n = Fsq . (N . n) ) by A6; AbsFMF . n = abs (FMF . n) by SEQFUNC:def_4; then A64: AbsFMF . n = abs ((Fsq . (N . (n + 1))) - (Fsq . (N . n))) by A63, A10; A65: ( Fsq . (N . (n + 1)) in Lp_Functions (M,k) & Fsq . (N . (n + 1)) in Sq . (N . (n + 1)) & Fsq . (N . n) in Lp_Functions (M,k) & Fsq . (N . n) in Sq . (N . n) ) by A3; then (- 1) (#) (Fsq . (N . n)) in (- 1) * (Sq . (N . n)) by Th54; then (Fsq . (N . (n + 1))) - (Fsq . (N . n)) in (Sq . (N . (n + 1))) + ((- 1) * (Sq . (N . n))) by Th54, A65; then (Fsq . (N . (n + 1))) - (Fsq . (N . n)) in (Sq . (N . (n + 1))) - (Sq . (N . n)) by RLVECT_1:16; then A66: ex r being Real st ( 0 <= r & r = Integral (M,((abs ((Fsq . (N . (n + 1))) - (Fsq . (N . n)))) to_power k)) & ||.((Sq . (N . (n + 1))) - (Sq . (N . n))).|| = r to_power (1 / k) ) by Th53; PAbsFMF . n = (KPAbsFMF . n) to_power (1 / k) by A45; hence PAbsFMF . n = ||.((Sq . (N . (n + 1))) - (Sq . (N . n))).|| by A66, A64, A43; ::_thesis: verum end; 1 / 2 < 1 ; then abs (1 / 2) < 1 by ABSVALUE:def_1; then A67: ( (1 / 2) GeoSeq is summable & Sum ((1 / 2) GeoSeq) = 1 / (1 - (1 / 2)) ) by SERIES_1:24; for n being Element of NAT holds ( 0 <= PAbsFMF . n & PAbsFMF . n <= ((1 / 2) GeoSeq) . n ) proof let n be Element of NAT ; ::_thesis: ( 0 <= PAbsFMF . n & PAbsFMF . n <= ((1 / 2) GeoSeq) . n ) A68: PAbsFMF . n = ||.((Sq . (N . (n + 1))) - (Sq . (N . n))).|| by A62; hence 0 <= PAbsFMF . n ; ::_thesis: PAbsFMF . n <= ((1 / 2) GeoSeq) . n ((1 / 2) GeoSeq) . n = (1 / 2) |^ n by PREPOWER:def_1 .= (1 / 2) to_power n by POWER:41 ; then A69: ((1 / 2) GeoSeq) . n = 2 to_power (- n) by POWER:32; N is Real_Sequence by FUNCT_2:7; then N . n < N . (n + 1) by SEQM_3:def_6; hence PAbsFMF . n <= ((1 / 2) GeoSeq) . n by A5, A68, A69; ::_thesis: verum end; then ( PAbsFMF is summable & Sum PAbsFMF <= Sum ((1 / 2) GeoSeq) ) by A67, SERIES_1:20; then Partial_Sums PAbsFMF is convergent by SERIES_1:def_2; then Partial_Sums PAbsFMF is bounded ; then consider Br being real number such that A70: for n being Element of NAT holds (Partial_Sums PAbsFMF) . n < Br by SEQ_2:def_3; for n being Element of NAT holds Ir . n < ((RF0 to_power (1 / k)) + Br) to_power k proof let n be Element of NAT ; ::_thesis: Ir . n < ((RF0 to_power (1 / k)) + Br) to_power k (Ir . n) to_power (1 / k) <= QAbsFMF . n by A48; then A71: (Ir . n) to_power (1 / k) <= (RF0 to_power (1 / k)) + ((Partial_Sums PAbsFMF) . n) by A47; (RF0 to_power (1 / k)) + ((Partial_Sums PAbsFMF) . n) < (RF0 to_power (1 / k)) + Br by A70, XREAL_1:8; then A72: (Ir . n) to_power (1 / k) < (RF0 to_power (1 / k)) + Br by A71, XXREAL_0:2; Ir . n = Integral (M,(Gp . n)) by A38; then Ir . n = Integral (M,((G . n) to_power k)) by A23; then A73: Ir . n = Integral (M,((abs (G . n)) to_power k)) by A17; A74: G . n in Lp_Functions (M,k) by A17; then 0 <= (Ir . n) to_power (1 / k) by Th49, A73, Th4; then ((Ir . n) to_power (1 / k)) to_power k < ((RF0 to_power (1 / k)) + Br) to_power k by A72, Th3; then (Ir . n) to_power ((1 / k) * k) < ((RF0 to_power (1 / k)) + Br) to_power k by A74, Th49, A73, HOLDER_1:2; then (Ir . n) to_power 1 < ((RF0 to_power (1 / k)) + Br) to_power k by XCMPLX_1:106; hence Ir . n < ((RF0 to_power (1 / k)) + Br) to_power k by POWER:25; ::_thesis: verum end; then A75: Ir is bounded_above by SEQ_2:def_3; for n, m being Element of NAT st n <= m holds Ir . n <= Ir . m proof let n, m be Element of NAT ; ::_thesis: ( n <= m implies Ir . n <= Ir . m ) assume n <= m ; ::_thesis: Ir . n <= Ir . m then A76: for x being Element of X st x in E holds (ExtGp . n) . x <= (ExtGp . m) . x by A28; A77: ( ExtGp . n is_measurable_on E & ExtGp . m is_measurable_on E & ExtGp . n is nonnegative & ExtGp . m is nonnegative ) by A26; A78: ( dom (ExtGp . n) = E & dom (ExtGp . m) = E ) by A26; then A79: ( (ExtGp . n) | E = ExtGp . n & (ExtGp . m) | E = ExtGp . m ) by RELAT_1:68; ( I . n = Integral (M,(ExtGp . n)) & I . m = Integral (M,(ExtGp . m)) ) by A38; hence Ir . n <= Ir . m by A76, A78, A77, A79, MESFUNC9:15; ::_thesis: verum end; then Ir is V169() by SEQM_3:6; then A80: ( I is convergent_to_finite_number & lim I = lim Ir ) by A75, RINFSUP2:14; reconsider LExtGp = lim ExtGp as PartFunc of X,ExtREAL ; A81: ( E = dom LExtGp & LExtGp is_measurable_on E ) by A26, A27, A37, MESFUNC8:25, MESFUNC8:def_9; A82: for x being set st x in dom LExtGp holds 0 <= LExtGp . x proof let x be set ; ::_thesis: ( x in dom LExtGp implies 0 <= LExtGp . x ) assume A83: x in dom LExtGp ; ::_thesis: 0 <= LExtGp . x then reconsider x1 = x as Element of X ; A84: x1 in E by A27, A83, MESFUNC8:def_9; now__::_thesis:_for_k1_being_Nat_holds_0_<=_(ExtGp_#_x1)_._k1 let k1 be Nat; ::_thesis: 0 <= (ExtGp # x1) . k1 reconsider k = k1 as Element of NAT by ORDINAL1:def_12; ExtGp # x1 is V169() by A35, A84; then A85: (ExtGp # x1) . 0 <= (ExtGp # x1) . k by RINFSUP2:7; 0 <= (ExtGp . 0) . x1 by A27, SUPINF_2:39; hence 0 <= (ExtGp # x1) . k1 by A85, MESFUNC5:def_13; ::_thesis: verum end; then 0 <= lim (ExtGp # x1) by A84, A37, MESFUNC9:10; hence 0 <= LExtGp . x by A83, MESFUNC8:def_9; ::_thesis: verum end; A86: eq_dom (LExtGp,+infty) = E /\ (eq_dom (LExtGp,+infty)) by A81, RELAT_1:132, XBOOLE_1:28; then reconsider EE = eq_dom (LExtGp,+infty) as Element of S by A81, MESFUNC1:33; reconsider E0 = E \ EE as Element of S ; E0 ` = (X \ E) \/ (X /\ EE) by XBOOLE_1:52; then A87: E0 ` = (E `) \/ EE by XBOOLE_1:28; M . EE = 0 by A38, A80, A81, A82, A86, MESFUNC9:13, SUPINF_2:52; then A88: EE is measure_zero of M by MEASURE1:def_7; E ` is Element of S by MEASURE1:34; then E ` is measure_zero of M by A4, MEASURE1:def_7; then E0 ` is measure_zero of M by A87, A88, MEASURE1:37; then A89: M . (E0 `) = 0 by MEASURE1:def_7; A90: for x being Element of X st x in E0 holds LExtGp . x in REAL proof let x be Element of X; ::_thesis: ( x in E0 implies LExtGp . x in REAL ) assume x in E0 ; ::_thesis: LExtGp . x in REAL then ( x in E & not x in EE ) by XBOOLE_0:def_5; then ( LExtGp . x <> +infty & 0 <= LExtGp . x ) by A81, A82, MESFUNC1:def_15; hence LExtGp . x in REAL by XXREAL_0:14; ::_thesis: verum end; A91: for x being Element of X st x in E0 holds ( Gp # x is convergent & lim (Gp # x) = lim (ExtGp # x) ) proof let x be Element of X; ::_thesis: ( x in E0 implies ( Gp # x is convergent & lim (Gp # x) = lim (ExtGp # x) ) ) assume A92: x in E0 ; ::_thesis: ( Gp # x is convergent & lim (Gp # x) = lim (ExtGp # x) ) then A93: x in E by XBOOLE_0:def_5; then LExtGp . x = lim (ExtGp # x) by A81, MESFUNC8:def_9; then A94: lim (ExtGp # x) in REAL by A90, A92; ExtGp # x is convergent by A37, A93; then A95: ex g being real number st ( lim (ExtGp # x) = g & ( for p being real number st 0 < p holds ex n being Nat st for m being Nat st n <= m holds |.(((ExtGp # x) . m) - (lim (ExtGp # x))).| < p ) & ExtGp # x is convergent_to_finite_number ) by A94, MESFUNC5:def_12; ExtGp # x = Gp # x by MESFUN7C:1; hence ( Gp # x is convergent & lim (Gp # x) = lim (ExtGp # x) ) by A95, RINFSUP2:15; ::_thesis: verum end; A96: for x being Element of X st x in E0 holds for n being Element of NAT holds (Gp # x) . n = ((G # x) . n) to_power k proof let x be Element of X; ::_thesis: ( x in E0 implies for n being Element of NAT holds (Gp # x) . n = ((G # x) . n) to_power k ) assume A97: x in E0 ; ::_thesis: for n being Element of NAT holds (Gp # x) . n = ((G # x) . n) to_power k hereby ::_thesis: verum let n be Element of NAT ; ::_thesis: (Gp # x) . n = ((G # x) . n) to_power k x in E by A97, XBOOLE_0:def_5; then x in dom (G . n) by A17; then A98: x in dom ((G . n) to_power k) by MESFUN6C:def_4; (Gp # x) . n = (Gp . n) . x by SEQFUNC:def_10 .= ((G . n) to_power k) . x by A23 .= ((G . n) . x) to_power k by A98, MESFUN6C:def_4 ; hence (Gp # x) . n = ((G # x) . n) to_power k by SEQFUNC:def_10; ::_thesis: verum end; end; A99: for x being Element of X st x in E0 holds (Partial_Sums AbsFMF) # x is convergent proof let x be Element of X; ::_thesis: ( x in E0 implies (Partial_Sums AbsFMF) # x is convergent ) assume A100: x in E0 ; ::_thesis: (Partial_Sums AbsFMF) # x is convergent then A101: Gp # x is convergent by A91; A102: now__::_thesis:_for_n_being_Element_of_NAT_holds_0_<=_(G_#_x)_._n let n be Element of NAT ; ::_thesis: 0 <= (G # x) . n G . n is nonnegative by A17; then 0 <= (G . n) . x by MESFUNC6:51; hence 0 <= (G # x) . n by SEQFUNC:def_10; ::_thesis: verum end; for n being Element of NAT holds (Gp # x) . n = ((G # x) . n) to_power k by A100, A96; then A103: G # x is convergent by A101, A102, Th9; now__::_thesis:_for_s_being_real_number_st_0_<_s_holds_ ex_n_being_Element_of_NAT_st_ for_m_being_Element_of_NAT_st_n_<=_m_holds_ abs_((((Partial_Sums_AbsFMF)_#_x)_._m)_-_(((Partial_Sums_AbsFMF)_#_x)_._n))_<_s let s be real number ; ::_thesis: ( 0 < s implies ex n being Element of NAT st for m being Element of NAT st n <= m holds abs ((((Partial_Sums AbsFMF) # x) . m) - (((Partial_Sums AbsFMF) # x) . n)) < s ) assume 0 < s ; ::_thesis: ex n being Element of NAT st for m being Element of NAT st n <= m holds abs ((((Partial_Sums AbsFMF) # x) . m) - (((Partial_Sums AbsFMF) # x) . n)) < s then consider n being Element of NAT such that A104: for m being Element of NAT st n <= m holds abs (((G # x) . m) - ((G # x) . n)) < s by A103, SEQ_4:41; now__::_thesis:_for_m_being_Element_of_NAT_st_n_<=_m_holds_ abs_((((Partial_Sums_AbsFMF)_#_x)_._m)_-_(((Partial_Sums_AbsFMF)_#_x)_._n))_<_s let m be Element of NAT ; ::_thesis: ( n <= m implies abs ((((Partial_Sums AbsFMF) # x) . m) - (((Partial_Sums AbsFMF) # x) . n)) < s ) assume A105: n <= m ; ::_thesis: abs ((((Partial_Sums AbsFMF) # x) . m) - (((Partial_Sums AbsFMF) # x) . n)) < s x in E by A100, XBOOLE_0:def_5; then A106: ( x in dom (G . n) & x in dom (G . m) ) by A17; ( G . m = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . m) & G . n = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . n) ) by A16; then ( (G . m) . x = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . m) . x) & (G . n) . x = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . n) . x) ) by A106, VALUED_1:def_1; then ( (G # x) . m = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . m) . x) & (G # x) . n = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . n) . x) ) by SEQFUNC:def_10; then A107: ((G # x) . m) - ((G # x) . n) = (((Partial_Sums AbsFMF) . m) . x) - (((Partial_Sums AbsFMF) . n) . x) ; ( ((Partial_Sums AbsFMF) # x) . m = ((Partial_Sums AbsFMF) . m) . x & ((Partial_Sums AbsFMF) # x) . n = ((Partial_Sums AbsFMF) . n) . x ) by SEQFUNC:def_10; hence abs ((((Partial_Sums AbsFMF) # x) . m) - (((Partial_Sums AbsFMF) # x) . n)) < s by A104, A105, A107; ::_thesis: verum end; hence ex n being Element of NAT st for m being Element of NAT st n <= m holds abs ((((Partial_Sums AbsFMF) # x) . m) - (((Partial_Sums AbsFMF) # x) . n)) < s ; ::_thesis: verum end; hence (Partial_Sums AbsFMF) # x is convergent by SEQ_4:41; ::_thesis: verum end; A108: for x being Element of X st x in E0 holds Partial_Sums (abs (FMF # x)) = (Partial_Sums AbsFMF) # x proof let x be Element of X; ::_thesis: ( x in E0 implies Partial_Sums (abs (FMF # x)) = (Partial_Sums AbsFMF) # x ) assume x in E0 ; ::_thesis: Partial_Sums (abs (FMF # x)) = (Partial_Sums AbsFMF) # x then A109: x in E by XBOOLE_0:def_5; defpred S1[ Nat] means (Partial_Sums (abs (FMF # x))) . $1 = ((Partial_Sums AbsFMF) # x) . $1; (Partial_Sums (abs (FMF # x))) . 0 = (abs (FMF # x)) . 0 by SERIES_1:def_1 .= abs ((FMF # x) . 0) by VALUED_1:18 .= abs ((FMF . 0) . x) by SEQFUNC:def_10 .= (abs (FMF . 0)) . x by VALUED_1:18 .= (AbsFMF . 0) . x by SEQFUNC:def_4 .= ((Partial_Sums AbsFMF) . 0) . x by MESFUN9C:def_2 .= ((Partial_Sums AbsFMF) # x) . 0 by SEQFUNC:def_10 ; then A110: S1[ 0 ] ; A111: now__::_thesis:_for_n_being_Element_of_NAT_st_S1[n]_holds_ S1[n_+_1] let n be Element of NAT ; ::_thesis: ( S1[n] implies S1[n + 1] ) assume A112: S1[n] ; ::_thesis: S1[n + 1] A113: (Partial_Sums AbsFMF) . (n + 1) = ((Partial_Sums AbsFMF) . n) + (AbsFMF . (n + 1)) by MESFUN9C:def_2; dom (AbsFMF . 0) = E by A13; then A114: x in dom ((Partial_Sums AbsFMF) . (n + 1)) by A109, MESFUN9C:11; A115: (abs (FMF # x)) . (n + 1) = abs ((FMF # x) . (n + 1)) by VALUED_1:18 .= abs ((FMF . (n + 1)) . x) by SEQFUNC:def_10 .= (abs (FMF . (n + 1))) . x by VALUED_1:18 .= (AbsFMF . (n + 1)) . x by SEQFUNC:def_4 ; (Partial_Sums (abs (FMF # x))) . (n + 1) = ((Partial_Sums (abs (FMF # x))) . n) + ((abs (FMF # x)) . (n + 1)) by SERIES_1:def_1 .= (((Partial_Sums AbsFMF) . n) . x) + ((AbsFMF . (n + 1)) . x) by A112, A115, SEQFUNC:def_10 .= ((Partial_Sums AbsFMF) . (n + 1)) . x by A113, A114, VALUED_1:def_1 .= ((Partial_Sums AbsFMF) # x) . (n + 1) by SEQFUNC:def_10 ; hence S1[n + 1] ; ::_thesis: verum end; for n being Element of NAT holds S1[n] from NAT_1:sch_1(A110, A111); hence Partial_Sums (abs (FMF # x)) = (Partial_Sums AbsFMF) # x by FUNCT_2:63; ::_thesis: verum end; A116: for x being Element of X st x in E0 holds for n being Element of NAT holds (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) proof let x be Element of X; ::_thesis: ( x in E0 implies for n being Element of NAT holds (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) ) assume x in E0 ; ::_thesis: for n being Element of NAT holds (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) then A117: x in E by XBOOLE_0:def_5; defpred S1[ Nat] means (F1 # x) . ($1 + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . $1); dom (FMF . 0) = E by A11; then A118: x in dom ((F1 . (0 + 1)) - (F1 . 0)) by A10, A117; (Partial_Sums (FMF # x)) . 0 = (FMF # x) . 0 by SERIES_1:def_1 .= (FMF . 0) . x by SEQFUNC:def_10 .= ((F1 . (0 + 1)) - (F1 . 0)) . x by A10 ; then A119: (Partial_Sums (FMF # x)) . 0 = ((F1 . (0 + 1)) . x) - ((F1 . 0) . x) by A118, VALUED_1:13; ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . 0) = ((F1 . 0) . x) + ((Partial_Sums (FMF # x)) . 0) by SEQFUNC:def_10; then A120: S1[ 0 ] by A119, SEQFUNC:def_10; A121: now__::_thesis:_for_n_being_Element_of_NAT_st_S1[n]_holds_ S1[n_+_1] let n be Element of NAT ; ::_thesis: ( S1[n] implies S1[n + 1] ) assume A122: S1[n] ; ::_thesis: S1[n + 1] dom (FMF . (n + 1)) = E by A11; then A123: x in dom ((F1 . ((n + 1) + 1)) - (F1 . (n + 1))) by A10, A117; (FMF # x) . (n + 1) = (FMF . (n + 1)) . x by SEQFUNC:def_10 .= ((F1 . ((n + 1) + 1)) - (F1 . (n + 1))) . x by A10 ; then A124: (FMF # x) . (n + 1) = ((F1 . ((n + 1) + 1)) . x) - ((F1 . (n + 1)) . x) by A123, VALUED_1:13; ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . (n + 1)) = ((F1 # x) . 0) + (((Partial_Sums (FMF # x)) . n) + ((FMF # x) . (n + 1))) by SERIES_1:def_1 .= (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n)) + ((FMF # x) . (n + 1)) .= ((F1 . (n + 1)) . x) + ((FMF # x) . (n + 1)) by A122, SEQFUNC:def_10 ; hence S1[n + 1] by A124, SEQFUNC:def_10; ::_thesis: verum end; for n being Element of NAT holds S1[n] from NAT_1:sch_1(A120, A121); hence for n being Element of NAT holds (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) ; ::_thesis: verum end; A125: for x being Element of X st x in E0 holds F1 # x is convergent proof let x be Element of X; ::_thesis: ( x in E0 implies F1 # x is convergent ) assume A126: x in E0 ; ::_thesis: F1 # x is convergent then Partial_Sums (abs (FMF # x)) = (Partial_Sums AbsFMF) # x by A108; then Partial_Sums (abs (FMF # x)) is convergent by A126, A99; then abs (FMF # x) is summable by SERIES_1:def_2; then FMF # x is absolutely_summable by SERIES_1:def_4; then FMF # x is summable ; then A127: Partial_Sums (FMF # x) is convergent by SERIES_1:def_2; now__::_thesis:_for_s_being_real_number_st_0_<_s_holds_ ex_n_being_Element_of_NAT_st_ for_m_being_Element_of_NAT_st_n_<=_m_holds_ abs_(((F1_#_x)_._m)_-_((F1_#_x)_._n))_<_s let s be real number ; ::_thesis: ( 0 < s implies ex n being Element of NAT st for m being Element of NAT st n <= m holds abs (((F1 # x) . m) - ((F1 # x) . n)) < s ) assume 0 < s ; ::_thesis: ex n being Element of NAT st for m being Element of NAT st n <= m holds abs (((F1 # x) . m) - ((F1 # x) . n)) < s then consider n being Element of NAT such that A128: for m being Element of NAT st n <= m holds abs (((Partial_Sums (FMF # x)) . m) - ((Partial_Sums (FMF # x)) . n)) < s by A127, SEQ_4:41; set n1 = n + 1; now__::_thesis:_for_m1_being_Element_of_NAT_st_n_+_1_<=_m1_holds_ abs_(((F1_#_x)_._m1)_-_((F1_#_x)_._(n_+_1)))_<_s let m1 be Element of NAT ; ::_thesis: ( n + 1 <= m1 implies abs (((F1 # x) . m1) - ((F1 # x) . (n + 1))) < s ) assume A129: n + 1 <= m1 ; ::_thesis: abs (((F1 # x) . m1) - ((F1 # x) . (n + 1))) < s 1 <= n + 1 by NAT_1:11; then reconsider m = m1 - 1 as Element of NAT by A129, NAT_1:21, XXREAL_0:2; (n + 1) - 1 <= m1 - 1 by A129, XREAL_1:9; then A130: abs (((Partial_Sums (FMF # x)) . m) - ((Partial_Sums (FMF # x)) . n)) < s by A128; m1 = m + 1 ; then ( (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) & (F1 # x) . m1 = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . m) ) by A116, A126; hence abs (((F1 # x) . m1) - ((F1 # x) . (n + 1))) < s by A130; ::_thesis: verum end; hence ex n being Element of NAT st for m being Element of NAT st n <= m holds abs (((F1 # x) . m) - ((F1 # x) . n)) < s ; ::_thesis: verum end; hence F1 # x is convergent by SEQ_4:41; ::_thesis: verum end; set F2 = F1 || E0; A131: for x being Element of X st x in E0 holds (F1 || E0) # x is convergent proof let x be Element of X; ::_thesis: ( x in E0 implies (F1 || E0) # x is convergent ) assume A132: x in E0 ; ::_thesis: (F1 || E0) # x is convergent then F1 # x is convergent by A125; hence (F1 || E0) # x is convergent by A132, MESFUN9C:1; ::_thesis: verum end; A133: for x being Element of X st x in E0 holds (F1 || E0) # x = F1 # x proof let x be Element of X; ::_thesis: ( x in E0 implies (F1 || E0) # x = F1 # x ) assume A134: x in E0 ; ::_thesis: (F1 || E0) # x = F1 # x now__::_thesis:_for_n_being_Element_of_NAT_holds_((F1_||_E0)_#_x)_._n_=_(F1_#_x)_._n let n be Element of NAT ; ::_thesis: ((F1 || E0) # x) . n = (F1 # x) . n ((F1 || E0) # x) . n = ((F1 || E0) . n) . x by SEQFUNC:def_10 .= ((F1 . n) | E0) . x by MESFUN9C:def_1 .= (F1 . n) . x by A134, FUNCT_1:49 ; hence ((F1 || E0) # x) . n = (F1 # x) . n by SEQFUNC:def_10; ::_thesis: verum end; hence (F1 || E0) # x = F1 # x by FUNCT_2:63; ::_thesis: verum end; A135: for n being Nat holds ( dom ((F1 || E0) . n) = E0 & (F1 || E0) . n is_measurable_on E0 ) proof let n be Nat; ::_thesis: ( dom ((F1 || E0) . n) = E0 & (F1 || E0) . n is_measurable_on E0 ) A136: dom (F1 . 0) = E by A7; dom ((F1 || E0) . n) = dom ((F1 . n) | E0) by MESFUN9C:def_1; then dom ((F1 || E0) . n) = (dom (F1 . n)) /\ E0 by RELAT_1:61; then dom ((F1 || E0) . n) = E /\ E0 by A7; hence dom ((F1 || E0) . n) = E0 by XBOOLE_1:28, XBOOLE_1:36; ::_thesis: (F1 || E0) . n is_measurable_on E0 for m being Nat holds F1 . m is_measurable_on E0 proof let m be Nat; ::_thesis: F1 . m is_measurable_on E0 F1 . m is_measurable_on E by A7; hence F1 . m is_measurable_on E0 by MESFUNC6:16, XBOOLE_1:36; ::_thesis: verum end; hence (F1 || E0) . n is_measurable_on E0 by A136, MESFUN9C:4, XBOOLE_1:36; ::_thesis: verum end; reconsider F2 = F1 || E0 as with_the_same_dom Functional_Sequence of X,REAL by MESFUN9C:2; A137: for n being Nat holds ( F2 . n in Lp_Functions (M,k) & F2 . n in Sq . (N . n) ) proof let n1 be Nat; ::_thesis: ( F2 . n1 in Lp_Functions (M,k) & F2 . n1 in Sq . (N . n1) ) F2 . n1 = (F1 . n1) | E0 by MESFUN9C:def_1; then abs (F2 . n1) = (abs (F1 . n1)) | E0 by Th13; then A138: ((abs (F1 . n1)) to_power k) | E0 = (abs (F2 . n1)) to_power k by Th20; A139: ( F2 . n1 is_measurable_on E0 & dom (F2 . n1) = E0 ) by A135; F1 . n1 in Lp_Functions (M,k) by A7; then ex FMF being PartFunc of X,REAL st ( F1 . n1 = FMF & ex ND being Element of S st ( M . (ND `) = 0 & dom FMF = ND & FMF is_measurable_on ND & (abs FMF) to_power k is_integrable_on M ) ) ; then (abs (F2 . n1)) to_power k is_integrable_on M by A138, MESFUNC6:91; hence A140: F2 . n1 in Lp_Functions (M,k) by A139, A89; ::_thesis: F2 . n1 in Sq . (N . n1) reconsider n = n1 as Element of NAT by ORDINAL1:def_12; set m = N . n; F1 . n = Fsq . (N . n) by A6; then A141: ( F1 . n in Sq . (N . n) & Sq . (N . n) = a.e-eq-class_Lp ((F1 . n),M,k) ) by A3; reconsider EB = E0 ` as Element of S by MEASURE1:34; (F2 . n) | (EB `) = F2 . n by A139, RELAT_1:68; then (F2 . n) | (EB `) = (F1 . n) | (EB `) by MESFUN9C:def_1; then F2 . n a.e.= F1 . n,M by A89, LPSPACE1:def_10; hence F2 . n1 in Sq . (N . n1) by A140, A141, Th36; ::_thesis: verum end; A142: dom (lim F2) = dom (F2 . 0) by MESFUNC8:def_9; then A143: dom (lim F2) = E0 by A135; A144: for x being Element of X st x in E0 holds (lim F2) . x = lim (F2 # x) proof let x be Element of X; ::_thesis: ( x in E0 implies (lim F2) . x = lim (F2 # x) ) assume x in E0 ; ::_thesis: (lim F2) . x = lim (F2 # x) then ( (lim F2) . x = lim (R_EAL (F2 # x)) & F2 # x is convergent ) by A143, A131, MESFUN7C:14; hence (lim F2) . x = lim (F2 # x) by RINFSUP2:14; ::_thesis: verum end; now__::_thesis:_for_y_being_set_st_y_in_rng_(lim_F2)_holds_ y_in_REAL let y be set ; ::_thesis: ( y in rng (lim F2) implies y in REAL ) assume y in rng (lim F2) ; ::_thesis: y in REAL then consider x being Element of X such that A145: ( x in dom (lim F2) & y = (lim F2) . x ) by PARTFUN1:3; y = lim (F2 # x) by A145, A143, A144; hence y in REAL ; ::_thesis: verum end; then rng (lim F2) c= REAL by TARSKI:def_3; then reconsider F = lim F2 as PartFunc of X,REAL by A142, RELSET_1:4; A146: dom (LExtGp | E0) = E /\ E0 by A81, RELAT_1:61; then A147: dom (LExtGp | E0) = E0 by XBOOLE_1:28, XBOOLE_1:36; now__::_thesis:_for_y_being_set_st_y_in_rng_(LExtGp_|_E0)_holds_ y_in_REAL let y be set ; ::_thesis: ( y in rng (LExtGp | E0) implies y in REAL ) assume y in rng (LExtGp | E0) ; ::_thesis: y in REAL then consider x being Element of X such that A148: ( x in dom (LExtGp | E0) & y = (LExtGp | E0) . x ) by PARTFUN1:3; y = LExtGp . x by A147, A148, FUNCT_1:49; hence y in REAL by A147, A148, A90; ::_thesis: verum end; then rng (LExtGp | E0) c= REAL by TARSKI:def_3; then reconsider gp = LExtGp | E0 as PartFunc of X,REAL by A146, RELSET_1:4; A149: for x being Element of X st x in E0 holds gp . x = lim (Gp # x) proof let x be Element of X; ::_thesis: ( x in E0 implies gp . x = lim (Gp # x) ) assume A150: x in E0 ; ::_thesis: gp . x = lim (Gp # x) then x in dom LExtGp by A81, XBOOLE_0:def_5; then LExtGp . x = lim (ExtGp # x) by MESFUNC8:def_9; then gp . x = lim (ExtGp # x) by A150, FUNCT_1:49; hence gp . x = lim (Gp # x) by A91, A150; ::_thesis: verum end; LExtGp is nonnegative by A82, SUPINF_2:52; then LExtGp is_integrable_on M by A80, A38, A81, Th2; then R_EAL gp is_integrable_on M by MESFUNC5:97; then A151: gp is_integrable_on M by MESFUNC6:def_4; A152: dom (F2 . 0) = E0 by A135; then A153: dom F = E0 by MESFUNC8:def_9; then A154: E0 = dom (abs F) by VALUED_1:def_11; then A155: E0 = dom ((abs F) to_power k) by MESFUN6C:def_4; A156: for x being Element of X for n being Element of NAT st x in E0 holds (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n proof let x be Element of X; ::_thesis: for n being Element of NAT st x in E0 holds (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n let n be Element of NAT ; ::_thesis: ( x in E0 implies (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n ) assume A157: x in E0 ; ::_thesis: (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n then x in E by XBOOLE_0:def_5; then A158: x in dom (G . n) by A17; G . n = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . n) by A16; then (G . n) . x = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . n) . x) by A158, VALUED_1:def_1; then A159: (G . n) . x = (abs ((F1 . 0) . x)) + (((Partial_Sums AbsFMF) . n) . x) by VALUED_1:18; (G # x) . n = (G . n) . x by SEQFUNC:def_10 .= (abs ((F1 . 0) . x)) + (((Partial_Sums AbsFMF) # x) . n) by A159, SEQFUNC:def_10 .= (abs ((F1 # x) . 0)) + (((Partial_Sums AbsFMF) # x) . n) by SEQFUNC:def_10 ; then A160: (G # x) . n = (abs ((F1 # x) . 0)) + ((Partial_Sums (abs (FMF # x))) . n) by A108, A157; abs ((Partial_Sums (FMF # x)) . n) <= (Partial_Sums (abs (FMF # x))) . n by Lm1; hence (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n by A160, XREAL_1:6; ::_thesis: verum end; A161: for x being Element of X for n being Element of NAT st x in E0 holds (abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n))) to_power k <= (Gp # x) . n proof let x be Element of X; ::_thesis: for n being Element of NAT st x in E0 holds (abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n))) to_power k <= (Gp # x) . n let n be Element of NAT ; ::_thesis: ( x in E0 implies (abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n))) to_power k <= (Gp # x) . n ) assume A162: x in E0 ; ::_thesis: (abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n))) to_power k <= (Gp # x) . n then A163: (Gp # x) . n = ((G # x) . n) to_power k by A96; A164: (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n by A156, A162; abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n)) <= (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) by COMPLEX1:56; then A165: abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n by A164, XXREAL_0:2; 0 <= abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n)) by COMPLEX1:46; hence (abs (((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n))) to_power k <= (Gp # x) . n by A163, A165, HOLDER_1:3; ::_thesis: verum end; A166: for x being Element of X for n being Element of NAT st x in E0 holds (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n proof let x be Element of X; ::_thesis: for n being Element of NAT st x in E0 holds (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n let n be Element of NAT ; ::_thesis: ( x in E0 implies (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n ) assume A167: x in E0 ; ::_thesis: (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n then A168: F1 # x = F2 # x by A133; percases ( n = 0 or n <> 0 ) ; supposeA169: n = 0 ; ::_thesis: (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n A170: (Gp # x) . n = ((G # x) . n) to_power k by A167, A96; A171: (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n by A156, A167; 0 <= abs ((Partial_Sums (FMF # x)) . n) by COMPLEX1:46; then 0 + (abs ((F1 # x) . 0)) <= (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) by XREAL_1:6; then A172: abs ((F1 # x) . 0) <= (G # x) . n by A171, XXREAL_0:2; 0 <= abs ((F1 # x) . 0) by COMPLEX1:46; hence (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n by A168, A169, A170, A172, HOLDER_1:3; ::_thesis: verum end; suppose n <> 0 ; ::_thesis: (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n then consider m being Nat such that A173: n = m + 1 by NAT_1:6; reconsider m = m as Element of NAT by ORDINAL1:def_12; (F1 # x) . (m + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . m) by A116, A167; then A174: (abs ((F1 # x) . (m + 1))) to_power k <= (Gp # x) . m by A161, A167; x in E by A167, XBOOLE_0:def_5; then A175: ExtGp # x is V169() by A35; m <= m + 1 by NAT_1:11; then A176: (ExtGp # x) . m <= (ExtGp # x) . (m + 1) by A175, RINFSUP2:7; ExtGp # x = Gp # x by MESFUN7C:1; hence (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n by A168, A173, A174, A176, XXREAL_0:2; ::_thesis: verum end; end; end; A177: for x being Element of X st x in E0 holds abs (((abs F) to_power k) . x) <= gp . x proof let x be Element of X; ::_thesis: ( x in E0 implies abs (((abs F) to_power k) . x) <= gp . x ) assume A178: x in E0 ; ::_thesis: abs (((abs F) to_power k) . x) <= gp . x then A179: Gp # x is convergent by A91; deffunc H8( set ) -> Element of REAL = ((abs (F2 # x)) . $1) to_power k; consider s being Real_Sequence such that A180: for n being Element of NAT holds s . n = H8(n) from SEQ_1:sch_1(); A181: gp . x = lim (Gp # x) by A149, A178; A182: ((abs F) to_power k) . x = ((abs F) . x) to_power k by A155, A178, MESFUN6C:def_4 .= (abs (F . x)) to_power k by A154, A178, VALUED_1:def_11 .= (abs (lim (F2 # x))) to_power k by A178, A144 .= (lim (abs (F2 # x))) to_power k by A131, A178, SEQ_4:14 ; A183: now__::_thesis:_for_n_being_Element_of_NAT_holds_0_<=_(abs_(F2_#_x))_._n let n be Element of NAT ; ::_thesis: 0 <= (abs (F2 # x)) . n 0 <= abs ((F2 # x) . n) by COMPLEX1:46; hence 0 <= (abs (F2 # x)) . n by VALUED_1:18; ::_thesis: verum end; abs (F2 # x) is convergent by A178, A131, SEQ_4:13; then A184: ( s is convergent & (lim (abs (F2 # x))) to_power k = lim s ) by A183, A180, HOLDER_1:10; now__::_thesis:_for_n_being_Element_of_NAT_holds_s_._n_<=_(Gp_#_x)_._n let n be Element of NAT ; ::_thesis: s . n <= (Gp # x) . n (abs ((F2 # x) . n)) to_power k <= (Gp # x) . n by A166, A178; then ((abs (F2 # x)) . n) to_power k <= (Gp # x) . n by VALUED_1:18; hence s . n <= (Gp # x) . n by A180; ::_thesis: verum end; then A185: ((abs F) to_power k) . x <= gp . x by A184, A181, A182, A179, SEQ_2:18; 0 <= ((abs F) to_power k) . x by MESFUNC6:51; hence abs (((abs F) to_power k) . x) <= gp . x by A185, ABSVALUE:def_1; ::_thesis: verum end; R_EAL F is_measurable_on E0 by A135, A152, A131, MESFUN7C:21; then A186: F is_measurable_on E0 by MESFUNC6:def_1; then A187: abs F is_measurable_on E0 by A153, MESFUNC6:48; dom (abs F) = E0 by A153, VALUED_1:def_11; then (abs F) to_power k is_measurable_on E0 by A187, MESFUN6C:29; then (abs F) to_power k is_integrable_on M by A147, A151, A155, A177, MESFUNC6:96; then A188: F in Lp_Functions (M,k) by A89, A153, A186; A189: for x being Element of X for n, m being Element of NAT st x in E0 & m <= n holds |.(((F1 # x) . n) - ((F1 # x) . m)).| to_power k <= (Gp # x) . n proof let x be Element of X; ::_thesis: for n, m being Element of NAT st x in E0 & m <= n holds |.(((F1 # x) . n) - ((F1 # x) . m)).| to_power k <= (Gp # x) . n let n1, m1 be Element of NAT ; ::_thesis: ( x in E0 & m1 <= n1 implies |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 ) assume A190: ( x in E0 & m1 <= n1 ) ; ::_thesis: |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 now__::_thesis:_|.(((F1_#_x)_._n1)_-_((F1_#_x)_._m1)).|_to_power_k_<=_(Gp_#_x)_._n1 percases ( m1 = 0 or m1 <> 0 ) ; supposeA191: m1 = 0 ; ::_thesis: |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 now__::_thesis:_|.(((F1_#_x)_._n1)_-_((F1_#_x)_._m1)).|_to_power_k_<=_(Gp_#_x)_._n1 percases ( n1 = 0 or n1 <> 0 ) ; supposeA192: n1 = 0 ; ::_thesis: |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 (G . n1) to_power k is nonnegative by A24; then Gp . n1 is nonnegative by A23; then 0 <= (Gp . n1) . x by MESFUNC6:51; then 0 <= (Gp # x) . n1 by SEQFUNC:def_10; hence |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 by A191, A192, COMPLEX1:44, POWER:def_2; ::_thesis: verum end; suppose n1 <> 0 ; ::_thesis: |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 then consider n being Nat such that A193: n1 = n + 1 by NAT_1:6; reconsider n = n as Element of NAT by ORDINAL1:def_12; A194: (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) by A190, A116; A195: (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) <= (G # x) . n by A156, A190; 0 <= abs ((F1 # x) . 0) by COMPLEX1:46; then (abs ((Partial_Sums (FMF # x)) . n)) + 0 <= (abs ((F1 # x) . 0)) + (abs ((Partial_Sums (FMF # x)) . n)) by XREAL_1:6; then A196: abs ((Partial_Sums (FMF # x)) . n) <= (G # x) . n by A195, XXREAL_0:2; 0 <= abs ((Partial_Sums (FMF # x)) . n) by COMPLEX1:46; then A197: |.((Partial_Sums (FMF # x)) . n).| to_power k <= ((G # x) . n) to_power k by A196, HOLDER_1:3; A198: (Gp # x) . n = ((G # x) . n) to_power k by A190, A96; x in E by A190, XBOOLE_0:def_5; then A199: ExtGp # x is V169() by A35; n <= n + 1 by NAT_1:11; then A200: (ExtGp # x) . n <= (ExtGp # x) . (n + 1) by A199, RINFSUP2:7; ExtGp # x = Gp # x by MESFUN7C:1; hence |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 by A191, A193, A200, A197, A198, A194, XXREAL_0:2; ::_thesis: verum end; end; end; hence |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 ; ::_thesis: verum end; supposeA201: m1 <> 0 ; ::_thesis: |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 then consider m being Nat such that A202: m1 = m + 1 by NAT_1:6; reconsider m = m as Element of NAT by ORDINAL1:def_12; 0 < n1 by A190, A201; then consider n being Nat such that A203: n1 = n + 1 by NAT_1:6; reconsider n = n as Element of NAT by ORDINAL1:def_12; A204: m1 - 1 <= n1 - 1 by A190, XREAL_1:9; x in E by A190, XBOOLE_0:def_5; then A205: x in dom (G . n) by A17; then A206: x in dom ((G . n) to_power k) by MESFUN6C:def_4; (Gp # x) . n = (Gp . n) . x by SEQFUNC:def_10; then (Gp # x) . n = ((G . n) to_power k) . x by A23; then A207: (Gp # x) . n = ((G . n) . x) to_power k by A206, MESFUN6C:def_4; G . n = (abs (F1 . 0)) + ((Partial_Sums AbsFMF) . n) by A16; then (G . n) . x = ((abs (F1 . 0)) . x) + (((Partial_Sums AbsFMF) . n) . x) by A205, VALUED_1:def_1 .= (abs ((F1 . 0) . x)) + (((Partial_Sums AbsFMF) . n) . x) by VALUED_1:18 ; then A208: (G . n) . x = (abs ((F1 . 0) . x)) + (((Partial_Sums AbsFMF) # x) . n) by SEQFUNC:def_10; A209: ( (F1 # x) . (n + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . n) & (F1 # x) . (m + 1) = ((F1 # x) . 0) + ((Partial_Sums (FMF # x)) . m) ) by A190, A116; A210: |.(((Partial_Sums (FMF # x)) . n) - ((Partial_Sums (FMF # x)) . m)).| <= (Partial_Sums (abs (FMF # x))) . n by Th10, A202, A203, A204; A211: (Partial_Sums (abs (FMF # x))) . n = ((Partial_Sums AbsFMF) # x) . n by A108, A190; 0 <= abs ((F1 . 0) . x) by COMPLEX1:46; then 0 + ((Partial_Sums (abs (FMF # x))) . n) <= (abs ((F1 . 0) . x)) + (((Partial_Sums AbsFMF) # x) . n) by A211, XREAL_1:6; then A212: |.(((F1 # x) . (n + 1)) - ((F1 # x) . (m + 1))).| <= (G . n) . x by A208, A209, A210, XXREAL_0:2; 0 <= |.(((F1 # x) . (n + 1)) - ((F1 # x) . (m + 1))).| by COMPLEX1:46; then A213: |.(((F1 # x) . (n + 1)) - ((F1 # x) . (m + 1))).| to_power k <= (Gp # x) . n by A207, A212, HOLDER_1:3; x in E by A190, XBOOLE_0:def_5; then A214: ExtGp # x is V169() by A35; n <= n + 1 by NAT_1:11; then A215: (ExtGp # x) . n <= (ExtGp # x) . (n + 1) by A214, RINFSUP2:7; ExtGp # x = Gp # x by MESFUN7C:1; hence |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 by A202, A203, A215, A213, XXREAL_0:2; ::_thesis: verum end; end; end; hence |.(((F1 # x) . n1) - ((F1 # x) . m1)).| to_power k <= (Gp # x) . n1 ; ::_thesis: verum end; A216: for x being Element of X for n being Nat st x in E0 holds |.((F . x) - ((F2 # x) . n)).| to_power k <= gp . x proof let x be Element of X; ::_thesis: for n being Nat st x in E0 holds |.((F . x) - ((F2 # x) . n)).| to_power k <= gp . x let n1 be Nat; ::_thesis: ( x in E0 implies |.((F . x) - ((F2 # x) . n1)).| to_power k <= gp . x ) assume A217: x in E0 ; ::_thesis: |.((F . x) - ((F2 # x) . n1)).| to_power k <= gp . x then A218: Gp # x is convergent by A91; A219: F1 # x = F2 # x by A133, A217; A220: F2 # x is convergent by A217, A131; reconsider n = n1 as Element of NAT by ORDINAL1:def_12; deffunc H8( Element of NAT ) -> Element of REAL = ((F2 # x) . $1) - ((F2 # x) . n); consider s0 being Real_Sequence such that A221: for j being Element of NAT holds s0 . j = H8(j) from SEQ_1:sch_1(); A222: now__::_thesis:_for_p_being_real_number_st_0_<_p_holds_ ex_n1_being_Element_of_NAT_st_ for_m_being_Element_of_NAT_st_n1_<=_m_holds_ abs_((s0_._m)_-_((lim_(F2_#_x))_-_((F2_#_x)_._n)))_<_p let p be real number ; ::_thesis: ( 0 < p implies ex n1 being Element of NAT st for m being Element of NAT st n1 <= m holds abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p ) assume 0 < p ; ::_thesis: ex n1 being Element of NAT st for m being Element of NAT st n1 <= m holds abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p then consider n1 being Element of NAT such that A223: for m being Element of NAT st n1 <= m holds abs (((F2 # x) . m) - (lim (F2 # x))) < p by A220, SEQ_2:def_7; take n1 = n1; ::_thesis: for m being Element of NAT st n1 <= m holds abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p thus for m being Element of NAT st n1 <= m holds abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p ::_thesis: verum proof let m be Element of NAT ; ::_thesis: ( n1 <= m implies abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p ) assume A224: n1 <= m ; ::_thesis: abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p (s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n)) = (((F2 # x) . m) - ((F2 # x) . n)) - ((lim (F2 # x)) - ((F2 # x) . n)) by A221; then (s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n)) = ((F2 # x) . m) - (lim (F2 # x)) ; hence abs ((s0 . m) - ((lim (F2 # x)) - ((F2 # x) . n))) < p by A224, A223; ::_thesis: verum end; end; then A225: s0 is convergent by SEQ_2:def_6; then lim s0 = (lim (F2 # x)) - ((F2 # x) . n) by A222, SEQ_2:def_7; then A226: lim (abs s0) = abs ((lim (F2 # x)) - ((F2 # x) . n)) by A225, SEQ_4:14; A227: abs s0 is convergent by A225; deffunc H9( Element of NAT ) -> Element of REAL = |.(((F2 # x) . $1) - ((F2 # x) . n)).| to_power k; consider s being Real_Sequence such that A228: for j being Element of NAT holds s . j = H9(j) from SEQ_1:sch_1(); A229: for j being Element of NAT st n <= j holds s . j <= (Gp # x) . j proof let j be Element of NAT ; ::_thesis: ( n <= j implies s . j <= (Gp # x) . j ) assume n <= j ; ::_thesis: s . j <= (Gp # x) . j then |.(((F2 # x) . j) - ((F2 # x) . n)).| to_power k <= (Gp # x) . j by A219, A217, A189; hence s . j <= (Gp # x) . j by A228; ::_thesis: verum end; A230: now__::_thesis:_for_n_being_Element_of_NAT_holds_0_<=_(abs_s0)_._n let n be Element of NAT ; ::_thesis: 0 <= (abs s0) . n 0 <= abs (s0 . n) by COMPLEX1:46; hence 0 <= (abs s0) . n by VALUED_1:18; ::_thesis: verum end; now__::_thesis:_for_j_being_Element_of_NAT_holds_s_._j_=_((abs_s0)_._j)_to_power_k let j be Element of NAT ; ::_thesis: s . j = ((abs s0) . j) to_power k thus s . j = |.(((F2 # x) . j) - ((F2 # x) . n)).| to_power k by A228 .= (abs (s0 . j)) to_power k by A221 .= ((abs s0) . j) to_power k by VALUED_1:18 ; ::_thesis: verum end; then A231: ( s is convergent & lim s = (lim (abs s0)) to_power k ) by A230, A227, HOLDER_1:10; then A232: ( s ^\ n is convergent & lim (s ^\ n) = lim s ) by SEQ_4:20; gp . x = lim (Gp # x) by A149, A217; then A233: ( (Gp # x) ^\ n is convergent & lim ((Gp # x) ^\ n) = gp . x ) by A218, SEQ_4:20; for j being Element of NAT holds (s ^\ n) . j <= ((Gp # x) ^\ n) . j proof let j be Element of NAT ; ::_thesis: (s ^\ n) . j <= ((Gp # x) ^\ n) . j ( (s ^\ n) . j = s . (n + j) & ((Gp # x) ^\ n) . j = (Gp # x) . (n + j) ) by NAT_1:def_3; hence (s ^\ n) . j <= ((Gp # x) ^\ n) . j by A229, NAT_1:11; ::_thesis: verum end; then lim s <= gp . x by A232, A233, SEQ_2:18; hence |.((F . x) - ((F2 # x) . n1)).| to_power k <= gp . x by A226, A231, A144, A217; ::_thesis: verum end; deffunc H8( Nat) -> Element of bool [:X,REAL:] = |.(F - (F2 . $1)).| to_power k; consider FP being Functional_Sequence of X,REAL such that A234: for n being Nat holds FP . n = H8(n) from SEQFUNC:sch_1(); A235: for n being Nat holds dom (FP . n) = E0 proof let n1 be Nat; ::_thesis: dom (FP . n1) = E0 reconsider n = n1 as Element of NAT by ORDINAL1:def_12; A236: dom (F2 . n) = E0 by A135; dom (FP . n1) = dom ((abs (F - (F2 . n))) to_power k) by A234; then dom (FP . n1) = dom (abs (F - (F2 . n))) by MESFUN6C:def_4; then dom (FP . n1) = dom (F - (F2 . n)) by VALUED_1:def_11; then dom (FP . n1) = E0 /\ E0 by A236, A143, VALUED_1:12; hence dom (FP . n1) = E0 ; ::_thesis: verum end; then A237: E0 = dom (FP . 0) ; then A238: dom (lim FP) = E0 by MESFUNC8:def_9; for n, m being Nat holds dom (FP . n) = dom (FP . m) proof let n, m be Nat; ::_thesis: dom (FP . n) = dom (FP . m) thus dom (FP . n) = E0 by A235 .= dom (FP . m) by A235 ; ::_thesis: verum end; then reconsider FP = FP as with_the_same_dom Functional_Sequence of X,REAL by MESFUNC8:def_2; A239: for n being Nat holds FP . n is_measurable_on E0 proof let n1 be Nat; ::_thesis: FP . n1 is_measurable_on E0 reconsider n = n1 as Element of NAT by ORDINAL1:def_12; dom (F2 . n) = E0 by A135; then A240: dom (F - (F2 . n)) = E0 /\ E0 by A143, VALUED_1:12; ( F2 . n is_measurable_on E0 & dom (F2 . n) = E0 ) by A135; then F - (F2 . n) is_measurable_on E0 by A186, MESFUNC6:29; then A241: abs (F - (F2 . n)) is_measurable_on E0 by A240, MESFUNC6:48; dom (abs (F - (F2 . n))) = E0 by A240, VALUED_1:def_11; then (abs (F - (F2 . n))) to_power k is_measurable_on E0 by A241, MESFUN6C:29; hence FP . n1 is_measurable_on E0 by A234; ::_thesis: verum end; for x being Element of X for n being Nat st x in E0 holds |.(FP . n).| . x <= gp . x proof let x be Element of X; ::_thesis: for n being Nat st x in E0 holds |.(FP . n).| . x <= gp . x let n1 be Nat; ::_thesis: ( x in E0 implies |.(FP . n1).| . x <= gp . x ) reconsider n = n1 as Element of NAT by ORDINAL1:def_12; assume A242: x in E0 ; ::_thesis: |.(FP . n1).| . x <= gp . x then A243: x in dom (FP . n) by A235; then x in dom (|.(F - (F2 . n)).| to_power k) by A234; then x in dom |.(F - (F2 . n)).| by MESFUN6C:def_4; then A244: x in dom (F - (F2 . n)) by VALUED_1:def_11; A245: FP . n1 = |.(F - (F2 . n1)).| to_power k by A234; A246: 0 <= |.((F . x) - ((F2 . n1) . x)).| to_power k by Th4, COMPLEX1:46; |.(FP . n).| . x = |.((FP . n) . x).| by VALUED_1:18 .= |.((|.(F - (F2 . n1)).| . x) to_power k).| by A243, A245, MESFUN6C:def_4 .= |.(|.((F - (F2 . n1)) . x).| to_power k).| by VALUED_1:18 .= |.(|.((F . x) - ((F2 . n1) . x)).| to_power k).| by A244, VALUED_1:13 .= |.((F . x) - ((F2 . n1) . x)).| to_power k by A246, ABSVALUE:def_1 .= |.((F . x) - ((F2 # x) . n)).| to_power k by SEQFUNC:def_10 ; hence |.(FP . n1).| . x <= gp . x by A216, A242; ::_thesis: verum end; then consider Ip being Real_Sequence such that A247: ( ( for n being Nat holds Ip . n = Integral (M,(FP . n)) ) & ( ( for x being Element of X st x in E0 holds FP # x is convergent ) implies ( Ip is convergent & lim Ip = Integral (M,(lim FP)) ) ) ) by A147, A151, A237, A239, MESFUN9C:48; A248: for x being Element of X st x in E0 holds ( FP # x is convergent & lim (FP # x) = 0 ) proof let x be Element of X; ::_thesis: ( x in E0 implies ( FP # x is convergent & lim (FP # x) = 0 ) ) assume A249: x in E0 ; ::_thesis: ( FP # x is convergent & lim (FP # x) = 0 ) A250: for n being Element of NAT holds (FP # x) . n = |.((lim (F2 # x)) - ((F2 # x) . n)).| to_power k proof let n be Element of NAT ; ::_thesis: (FP # x) . n = |.((lim (F2 # x)) - ((F2 # x) . n)).| to_power k x in dom (FP . n) by A249, A235; then A251: x in dom (|.(F - (F2 . n)).| to_power k) by A234; then x in dom |.(F - (F2 . n)).| by MESFUN6C:def_4; then A252: x in dom (F - (F2 . n)) by VALUED_1:def_11; thus (FP # x) . n = (FP . n) . x by SEQFUNC:def_10 .= (|.(F - (F2 . n)).| to_power k) . x by A234 .= (|.(F - (F2 . n)).| . x) to_power k by A251, MESFUN6C:def_4 .= |.((F - (F2 . n)) . x).| to_power k by VALUED_1:18 .= |.((F . x) - ((F2 . n) . x)).| to_power k by A252, VALUED_1:13 .= |.((lim (F2 # x)) - ((F2 . n) . x)).| to_power k by A144, A249 .= |.((lim (F2 # x)) - ((F2 # x) . n)).| to_power k by SEQFUNC:def_10 ; ::_thesis: verum end; F2 # x is convergent by A249, A131; hence ( FP # x is convergent & lim (FP # x) = 0 ) by A250, Th11; ::_thesis: verum end; A253: for x being Element of X st x in dom (lim FP) holds 0 = (lim FP) . x proof let x be Element of X; ::_thesis: ( x in dom (lim FP) implies 0 = (lim FP) . x ) assume A254: x in dom (lim FP) ; ::_thesis: 0 = (lim FP) . x then A255: ( lim (FP # x) = 0 & FP # x is convergent ) by A248, A238; (lim FP) . x = lim (R_EAL (FP # x)) by A254, MESFUN7C:14; hence 0 = (lim FP) . x by A255, RINFSUP2:14; ::_thesis: verum end; a.e-eq-class_Lp (F,M,k) in CosetSet (M,k) by A188; then reconsider Sq0 = a.e-eq-class_Lp (F,M,k) as Point of (Lp-Space (M,k)) by Def11; A256: for n being Element of NAT holds Ip . n = ||.(Sq0 - (Sq . (N . n))).|| to_power k proof let n be Element of NAT ; ::_thesis: Ip . n = ||.(Sq0 - (Sq . (N . n))).|| to_power k set m = N . n; reconsider n1 = n as Nat ; A257: FP . n = (abs (F - (F2 . n1))) to_power k by A234; A258: ( F in Lp_Functions (M,k) & F in Sq0 ) by A188, Th38; ( F2 . n1 in Lp_Functions (M,k) & F2 . n1 in Sq . (N . n) ) by A137; then (- 1) (#) (F2 . n1) in (- 1) * (Sq . (N . n)) by Th54; then F - (F2 . n1) in Sq0 + ((- 1) * (Sq . (N . n))) by Th54, A258; then F - (F2 . n1) in Sq0 - (Sq . (N . n)) by RLVECT_1:16; then consider r being Real such that A259: ( 0 <= r & r = Integral (M,((abs (F - (F2 . n1))) to_power k)) & ||.(Sq0 - (Sq . (N . n))).|| = r to_power (1 / k) ) by Th53; ||.(Sq0 - (Sq . (N . n))).|| to_power k = r to_power ((1 / k) * k) by A259, HOLDER_1:2 .= r to_power 1 by XCMPLX_1:106 .= r by POWER:25 ; hence Ip . n = ||.(Sq0 - (Sq . (N . n))).|| to_power k by A259, A257, A247; ::_thesis: verum end; deffunc H9( Element of NAT ) -> Element of REAL = ||.(Sq0 - (Sq . (N . $1))).||; consider Iq being Real_Sequence such that A260: for n being Element of NAT holds Iq . n = H9(n) from SEQ_1:sch_1(); A261: now__::_thesis:_for_n_being_Nat_holds_Iq_._n_=_||.(Sq0_-_(Sq_._(N_._n))).|| let n be Nat; ::_thesis: Iq . n = ||.(Sq0 - (Sq . (N . n))).|| reconsider n0 = n as Element of NAT by ORDINAL1:def_12; Iq . n = ||.(Sq0 - (Sq . (N . n0))).|| by A260; hence Iq . n = ||.(Sq0 - (Sq . (N . n))).|| ; ::_thesis: verum end; ( Iq is convergent & lim Iq = 0 ) proof A262: for n being Element of NAT holds Ip . n >= 0 proof let n be Element of NAT ; ::_thesis: Ip . n >= 0 ||.(Sq0 - (Sq . (N . n))).|| to_power k >= 0 by Th4; hence Ip . n >= 0 by A256; ::_thesis: verum end; A263: for n being Element of NAT holds Iq . n = (Ip . n) to_power (1 / k) proof let n be Element of NAT ; ::_thesis: Iq . n = (Ip . n) to_power (1 / k) thus (Ip . n) to_power (1 / k) = (||.(Sq0 - (Sq . (N . n))).|| to_power k) to_power (1 / k) by A256 .= ||.(Sq0 - (Sq . (N . n))).|| to_power (k * (1 / k)) by HOLDER_1:2 .= ||.(Sq0 - (Sq . (N . n))).|| to_power 1 by XCMPLX_1:106 .= ||.(Sq0 - (Sq . (N . n))).|| by POWER:25 .= Iq . n by A261 ; ::_thesis: verum end; hence Iq is convergent by A262, A248, A247, HOLDER_1:10; ::_thesis: lim Iq = 0 lim Iq = (lim Ip) to_power (1 / k) by A248, A247, A262, A263, HOLDER_1:10; then lim Iq = 0 to_power (1 / k) by A248, A247, A253, A238, LPSPACE1:22; hence lim Iq = 0 by POWER:def_2; ::_thesis: verum end; hence Sq is convergent by A2, A261, Lm7; ::_thesis: verum end; registration let X be non empty set ; let S be SigmaField of X; let M be sigma_Measure of S; let k be geq_than_1 Real; cluster Lp-Space (M,k) -> non empty complete ; coherence Lp-Space (M,k) is complete proof for Sq being sequence of (Lp-Space (M,k)) st Sq is Cauchy_sequence_by_Norm holds Sq is convergent by Th70; hence Lp-Space (M,k) is complete by LOPBAN_1:def_15; ::_thesis: verum end; end; begin Lm8: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st f in L1_Functions M holds ( f is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st f in L1_Functions M holds ( f is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL st f in L1_Functions M holds ( f is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL st f in L1_Functions M holds ( f is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ) let f be PartFunc of X,REAL; ::_thesis: ( f in L1_Functions M implies ( f is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ) ) assume f in L1_Functions M ; ::_thesis: ( f is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ) then ex f2 being PartFunc of X,REAL st ( f = f2 & ex E being Element of S st ( M . E = 0 & dom f2 = E ` & f2 is_integrable_on M ) ) ; then consider D being Element of S such that A1: ( M . D = 0 & dom f = D ` & f is_integrable_on M ) ; thus f is_integrable_on M by A1; ::_thesis: ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) reconsider E = D ` as Element of S by MEASURE1:34; take E ; ::_thesis: ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) thus ( M . (E `) = 0 & dom f = E ) by A1; ::_thesis: f is_measurable_on E R_EAL f is_integrable_on M by A1, MESFUNC6:def_4; then ex B being Element of S st ( B = dom (R_EAL f) & R_EAL f is_measurable_on B ) by MESFUNC5:def_17; hence f is_measurable_on E by A1, MESFUNC6:def_1; ::_thesis: verum end; Lm9: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds (abs f) to_power k is_integrable_on M proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds (abs f) to_power k is_integrable_on M let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds (abs f) to_power k is_integrable_on M let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL for k being positive Real st f in Lp_Functions (M,k) holds (abs f) to_power k is_integrable_on M let f be PartFunc of X,REAL; ::_thesis: for k being positive Real st f in Lp_Functions (M,k) holds (abs f) to_power k is_integrable_on M let k be positive Real; ::_thesis: ( f in Lp_Functions (M,k) implies (abs f) to_power k is_integrable_on M ) assume f in Lp_Functions (M,k) ; ::_thesis: (abs f) to_power k is_integrable_on M then ex f2 being PartFunc of X,REAL st ( f = f2 & ex E being Element of S st ( M . (E `) = 0 & dom f2 = E & f2 is_measurable_on E & (abs f2) to_power k is_integrable_on M ) ) ; hence (abs f) to_power k is_integrable_on M ; ::_thesis: verum end; Lm10: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) let f be PartFunc of X,REAL; ::_thesis: ( ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) implies a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) ) assume A1: ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ; ::_thesis: a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) now__::_thesis:_for_x_being_set_st_x_in_a.e-eq-class_Lp_(f,M,1)_holds_ x_in_a.e-eq-class_(f,M) let x be set ; ::_thesis: ( x in a.e-eq-class_Lp (f,M,1) implies x in a.e-eq-class (f,M) ) assume x in a.e-eq-class_Lp (f,M,1) ; ::_thesis: x in a.e-eq-class (f,M) then consider h being PartFunc of X,REAL such that A2: ( x = h & h in Lp_Functions (M,1) & f a.e.= h,M ) ; A3: ex g being PartFunc of X,REAL st ( h = g & ex E being Element of S st ( M . (E `) = 0 & dom g = E & g is_measurable_on E & (abs g) to_power 1 is_integrable_on M ) ) by A2; then consider Eh being Element of S such that A4: ( M . (Eh `) = 0 & dom h = Eh & h is_measurable_on Eh & (abs h) to_power 1 is_integrable_on M ) ; A5: dom ((abs h) to_power 1) = dom (abs h) by MESFUN6C:def_4; for x being Element of X st x in dom ((abs h) to_power 1) holds ((abs h) to_power 1) . x = (abs h) . x proof let x be Element of X; ::_thesis: ( x in dom ((abs h) to_power 1) implies ((abs h) to_power 1) . x = (abs h) . x ) assume x in dom ((abs h) to_power 1) ; ::_thesis: ((abs h) to_power 1) . x = (abs h) . x then ((abs h) to_power 1) . x = ((abs h) . x) to_power 1 by MESFUN6C:def_4; hence ((abs h) to_power 1) . x = (abs h) . x by POWER:25; ::_thesis: verum end; then (abs h) to_power 1 = abs h by A5, PARTFUN1:5; then A6: h is_integrable_on M by A3, MESFUNC6:94; reconsider ND = Eh ` as Element of S by MEASURE1:34; ( M . ND = 0 & dom h = ND ` ) by A4; then A7: h in L1_Functions M by A6; ex E being Element of S st ( M . E = 0 & dom f = E ` & f is_integrable_on M ) proof consider Ef being Element of S such that A8: ( M . (Ef `) = 0 & Ef = dom f & f is_measurable_on Ef ) by A1; reconsider E = Ef ` as Element of S by MEASURE1:34; take E ; ::_thesis: ( M . E = 0 & dom f = E ` & f is_integrable_on M ) consider EE being Element of S such that A9: ( M . EE = 0 & f | (EE `) = h | (EE `) ) by A2, LPSPACE1:def_10; reconsider E1 = ND \/ EE as Element of S ; ( ND is measure_zero of M & EE is measure_zero of M ) by A4, A9, MEASURE1:def_7; then E1 is measure_zero of M by MEASURE1:37; then A10: M . E1 = 0 by MEASURE1:def_7; EE c= E1 by XBOOLE_1:7; then E1 ` c= EE ` by SUBSET_1:12; then A11: ( f | (E1 `) = (f | (EE `)) | (E1 `) & h | (E1 `) = (h | (EE `)) | (E1 `) ) by FUNCT_1:51; A12: ( dom (max+ (R_EAL f)) = Ef & dom (max- (R_EAL f)) = Ef ) by A8, MESFUNC2:def_2, MESFUNC2:def_3; A13: ( Ef = dom (R_EAL f) & R_EAL f is_measurable_on Ef ) by A8, MESFUNC6:def_1; then A14: ( max+ (R_EAL f) is_measurable_on Ef & max- (R_EAL f) is_measurable_on Ef ) by MESFUNC2:25, MESFUNC2:26; ( ( for x being Element of X holds 0. <= (max+ (R_EAL f)) . x ) & ( for x being Element of X holds 0. <= (max- (R_EAL f)) . x ) ) by MESFUNC2:12, MESFUNC2:13; then A15: ( max+ (R_EAL f) is nonnegative & max- (R_EAL f) is nonnegative ) by SUPINF_2:39; A16: Ef = (Ef /\ E1) \/ (Ef \ E1) by XBOOLE_1:51; reconsider E0 = Ef /\ E1 as Element of S ; A17: Ef \ E1 = Ef /\ (E1 `) by SUBSET_1:13; reconsider E2 = Ef \ E1 as Element of S ; ( max+ (R_EAL f) = (max+ (R_EAL f)) | (dom (max+ (R_EAL f))) & max- (R_EAL f) = (max- (R_EAL f)) | (dom (max- (R_EAL f))) ) by RELAT_1:69; then A18: ( integral+ (M,(max+ (R_EAL f))) = (integral+ (M,((max+ (R_EAL f)) | E0))) + (integral+ (M,((max+ (R_EAL f)) | E2))) & integral+ (M,(max- (R_EAL f))) = (integral+ (M,((max- (R_EAL f)) | E0))) + (integral+ (M,((max- (R_EAL f)) | E2))) ) by A12, A15, A16, A14, MESFUNC5:81, XBOOLE_1:89; A19: ( integral+ (M,((max+ (R_EAL f)) | E0)) >= 0 & integral+ (M,((max- (R_EAL f)) | E0)) >= 0 ) by A15, A14, A12, MESFUNC5:80; ( integral+ (M,((max+ (R_EAL f)) | E1)) = 0 & integral+ (M,((max- (R_EAL f)) | E1)) = 0 ) by A10, A12, A15, A14, MESFUNC5:82; then ( integral+ (M,((max+ (R_EAL f)) | E0)) = 0 & integral+ (M,((max- (R_EAL f)) | E0)) = 0 ) by A19, A12, A15, A14, MESFUNC5:83, XBOOLE_1:17; then A20: ( integral+ (M,(max+ (R_EAL f))) = integral+ (M,((max+ (R_EAL f)) | E2)) & integral+ (M,(max- (R_EAL f))) = integral+ (M,((max- (R_EAL f)) | E2)) ) by A18, XXREAL_3:4; A21: E2 c= E1 ` by A17, XBOOLE_1:17; then f | E2 = (h | (E1 `)) | E2 by A9, A11, FUNCT_1:51; then A22: (R_EAL f) | E2 = (R_EAL h) | E2 by A21, FUNCT_1:51; A23: ( (max+ (R_EAL f)) | E2 = max+ ((R_EAL f) | E2) & (max+ (R_EAL h)) | E2 = max+ ((R_EAL h) | E2) & (max- (R_EAL f)) | E2 = max- ((R_EAL f) | E2) & (max- (R_EAL h)) | E2 = max- ((R_EAL h) | E2) ) by MESFUNC5:28; A24: R_EAL h is_integrable_on M by A6, MESFUNC6:def_4; then A25: ( integral+ (M,(max+ (R_EAL h))) < +infty & integral+ (M,(max- (R_EAL h))) < +infty ) by MESFUNC5:def_17; ( integral+ (M,(max+ ((R_EAL h) | E2))) <= integral+ (M,(max+ (R_EAL h))) & integral+ (M,(max- ((R_EAL h) | E2))) <= integral+ (M,(max- (R_EAL h))) ) by A24, MESFUNC5:97; then ( integral+ (M,(max+ (R_EAL f))) < +infty & integral+ (M,(max- (R_EAL f))) < +infty ) by A20, A25, A23, A22, XXREAL_0:2; then R_EAL f is_integrable_on M by A13, MESFUNC5:def_17; hence ( M . E = 0 & dom f = E ` & f is_integrable_on M ) by A8, MESFUNC6:def_4; ::_thesis: verum end; then f in L1_Functions M ; hence x in a.e-eq-class (f,M) by A2, A7; ::_thesis: verum end; hence a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) by TARSKI:def_3; ::_thesis: verum end; Lm11: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL holds a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL holds a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL holds a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL holds a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) let f be PartFunc of X,REAL; ::_thesis: a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) now__::_thesis:_for_x_being_set_st_x_in_a.e-eq-class_(f,M)_holds_ x_in_a.e-eq-class_Lp_(f,M,1) let x be set ; ::_thesis: ( x in a.e-eq-class (f,M) implies x in a.e-eq-class_Lp (f,M,1) ) assume x in a.e-eq-class (f,M) ; ::_thesis: x in a.e-eq-class_Lp (f,M,1) then consider g being PartFunc of X,REAL such that A1: ( x = g & g in L1_Functions M & f in L1_Functions M & f a.e.= g,M ) ; A2: ex h being PartFunc of X,REAL st ( g = h & ex D being Element of S st ( M . D = 0 & dom h = D ` & h is_integrable_on M ) ) by A1; then R_EAL g is_integrable_on M by MESFUNC6:def_4; then consider A being Element of S such that A3: ( A = dom (R_EAL g) & R_EAL g is_measurable_on A ) by MESFUNC5:def_17; A4: ( A = dom g & g is_measurable_on A ) by A3, MESFUNC6:def_1; A5: M . (A `) = 0 by A2, A3; (abs g) to_power 1 = abs g by Th8; then (abs g) to_power 1 is_integrable_on M by A2, A4, MESFUNC6:94; then g in { p where p is PartFunc of X,REAL : ex Ep being Element of S st ( M . (Ep `) = 0 & dom p = Ep & p is_measurable_on Ep & (abs p) to_power 1 is_integrable_on M ) } by A4, A5; hence x in a.e-eq-class_Lp (f,M,1) by A1; ::_thesis: verum end; hence a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) by TARSKI:def_3; ::_thesis: verum end; Lm12: for X being non empty set for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) let M be sigma_Measure of S; ::_thesis: for f being PartFunc of X,REAL st ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) holds a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) let f be PartFunc of X,REAL; ::_thesis: ( ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) implies a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) ) assume ex E being Element of S st ( M . (E `) = 0 & E = dom f & f is_measurable_on E ) ; ::_thesis: a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) then A1: a.e-eq-class_Lp (f,M,1) c= a.e-eq-class (f,M) by Lm10; a.e-eq-class (f,M) c= a.e-eq-class_Lp (f,M,1) by Lm11; hence a.e-eq-class_Lp (f,M,1) = a.e-eq-class (f,M) by A1, XBOOLE_0:def_10; ::_thesis: verum end; theorem Th71: :: LPSPACE2:71 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds CosetSet M = CosetSet (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds CosetSet M = CosetSet (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds CosetSet M = CosetSet (M,1) let M be sigma_Measure of S; ::_thesis: CosetSet M = CosetSet (M,1) now__::_thesis:_for_x_being_set_st_x_in_CosetSet_M_holds_ x_in_CosetSet_(M,1) let x be set ; ::_thesis: ( x in CosetSet M implies x in CosetSet (M,1) ) assume x in CosetSet M ; ::_thesis: x in CosetSet (M,1) then consider g being PartFunc of X,REAL such that A1: ( x = a.e-eq-class (g,M) & g in L1_Functions M ) ; A2: ( g is_integrable_on M & ex E being Element of S st ( M . (E `) = 0 & E = dom g & g is_measurable_on E ) ) by A1, Lm8; then A3: x = a.e-eq-class_Lp (g,M,1) by A1, Lm12; (abs g) to_power 1 = abs g by Th8; then (abs g) to_power 1 is_integrable_on M by A2, MESFUNC6:94; then g in Lp_Functions (M,1) by A2; hence x in CosetSet (M,1) by A3; ::_thesis: verum end; then A4: CosetSet M c= CosetSet (M,1) by TARSKI:def_3; now__::_thesis:_for_x_being_set_st_x_in_CosetSet_(M,1)_holds_ x_in_CosetSet_M let x be set ; ::_thesis: ( x in CosetSet (M,1) implies x in CosetSet M ) assume x in CosetSet (M,1) ; ::_thesis: x in CosetSet M then consider g being PartFunc of X,REAL such that A5: ( x = a.e-eq-class_Lp (g,M,1) & g in Lp_Functions (M,1) ) ; consider E being Element of S such that A6: ( M . (E `) = 0 & dom g = E & g is_measurable_on E ) by A5, Th35; A7: x = a.e-eq-class (g,M) by A5, A6, Lm12; reconsider D = E ` as Element of S by MEASURE1:34; A8: ( M . D = 0 & dom g = D ` ) by A6; (abs g) to_power 1 is_integrable_on M by A5, Lm9; then abs g is_integrable_on M by Th8; then g is_integrable_on M by A6, MESFUNC6:94; then g in L1_Functions M by A8; hence x in CosetSet M by A7; ::_thesis: verum end; then CosetSet (M,1) c= CosetSet M by TARSKI:def_3; hence CosetSet M = CosetSet (M,1) by A4, XBOOLE_0:def_10; ::_thesis: verum end; theorem Th72: :: LPSPACE2:72 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds addCoset M = addCoset (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds addCoset M = addCoset (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds addCoset M = addCoset (M,1) let M be sigma_Measure of S; ::_thesis: addCoset M = addCoset (M,1) A1: CosetSet M = CosetSet (M,1) by Th71; now__::_thesis:_for_A,_B_being_Element_of_CosetSet_M_holds_(addCoset_M)_._(A,B)_=_(addCoset_(M,1))_._(A,B) let A, B be Element of CosetSet M; ::_thesis: (addCoset M) . (A,B) = (addCoset (M,1)) . (A,B) A in { (a.e-eq-class (f,M)) where f is PartFunc of X,REAL : f in L1_Functions M } ; then consider a being PartFunc of X,REAL such that A2: ( A = a.e-eq-class (a,M) & a in L1_Functions M ) ; B in { (a.e-eq-class (f,M)) where f is PartFunc of X,REAL : f in L1_Functions M } ; then consider b being PartFunc of X,REAL such that A3: ( B = a.e-eq-class (b,M) & b in L1_Functions M ) ; A4: ( A is Element of CosetSet (M,1) & B is Element of CosetSet (M,1) ) by Th71; A5: ( a in a.e-eq-class (a,M) & b in a.e-eq-class (b,M) ) by A2, A3, LPSPACE1:38; then A6: (addCoset M) . (A,B) = a.e-eq-class ((a + b),M) by A2, A3, LPSPACE1:def_15; a + b in L1_Functions M by A2, A3, LPSPACE1:23; then ex E being Element of S st ( M . (E `) = 0 & E = dom (a + b) & a + b is_measurable_on E ) by Lm8; then (addCoset M) . (A,B) = a.e-eq-class_Lp ((a + b),M,1) by A6, Lm12; hence (addCoset M) . (A,B) = (addCoset (M,1)) . (A,B) by A4, A5, A2, A3, Def8; ::_thesis: verum end; hence addCoset M = addCoset (M,1) by A1, BINOP_1:2; ::_thesis: verum end; theorem Th73: :: LPSPACE2:73 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds zeroCoset M = zeroCoset (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds zeroCoset M = zeroCoset (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds zeroCoset M = zeroCoset (M,1) let M be sigma_Measure of S; ::_thesis: zeroCoset M = zeroCoset (M,1) reconsider z = zeroCoset (M,1) as Element of CosetSet M by Th71; X --> 0 in Lp_Functions (M,1) by Th23; then ex E being Element of S st ( M . (E `) = 0 & dom (X --> 0) = E & X --> 0 is_measurable_on E ) by Th35; then A1: z = a.e-eq-class ((X --> 0),M) by Lm12; X --> 0 in L1_Functions M by Th56; hence zeroCoset M = zeroCoset (M,1) by A1, LPSPACE1:def_16; ::_thesis: verum end; theorem Th74: :: LPSPACE2:74 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds lmultCoset M = lmultCoset (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds lmultCoset M = lmultCoset (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds lmultCoset M = lmultCoset (M,1) let M be sigma_Measure of S; ::_thesis: lmultCoset M = lmultCoset (M,1) A1: CosetSet M = CosetSet (M,1) by Th71; now__::_thesis:_for_z_being_Element_of_REAL_ for_A_being_Element_of_CosetSet_M_holds_(lmultCoset_M)_._(z,A)_=_(lmultCoset_(M,1))_._(z,A) let z be Element of REAL ; ::_thesis: for A being Element of CosetSet M holds (lmultCoset M) . (z,A) = (lmultCoset (M,1)) . (z,A) let A be Element of CosetSet M; ::_thesis: (lmultCoset M) . (z,A) = (lmultCoset (M,1)) . (z,A) A in { (a.e-eq-class (f,M)) where f is PartFunc of X,REAL : f in L1_Functions M } ; then consider a being PartFunc of X,REAL such that A2: ( A = a.e-eq-class (a,M) & a in L1_Functions M ) ; A3: A is Element of CosetSet (M,1) by Th71; A4: a in A by A2, LPSPACE1:38; then A5: (lmultCoset M) . (z,A) = a.e-eq-class ((z (#) a),M) by LPSPACE1:def_17; z (#) a in L1_Functions M by A2, LPSPACE1:24; then ex E being Element of S st ( M . (E `) = 0 & E = dom (z (#) a) & z (#) a is_measurable_on E ) by Lm8; then (lmultCoset M) . (z,A) = a.e-eq-class_Lp ((z (#) a),M,1) by A5, Lm12; hence (lmultCoset M) . (z,A) = (lmultCoset (M,1)) . (z,A) by A3, A4, Def10; ::_thesis: verum end; hence lmultCoset M = lmultCoset (M,1) by A1, BINOP_1:2; ::_thesis: verum end; theorem Th75: :: LPSPACE2:75 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds Pre-L-Space M = Pre-Lp-Space (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds Pre-L-Space M = Pre-Lp-Space (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds Pre-L-Space M = Pre-Lp-Space (M,1) let M be sigma_Measure of S; ::_thesis: Pre-L-Space M = Pre-Lp-Space (M,1) A1: ( the carrier of (Pre-L-Space M) = CosetSet M & the addF of (Pre-L-Space M) = addCoset M & 0. (Pre-L-Space M) = zeroCoset M & the Mult of (Pre-L-Space M) = lmultCoset M ) by LPSPACE1:def_18; ( CosetSet M = CosetSet (M,1) & addCoset M = addCoset (M,1) & zeroCoset M = zeroCoset (M,1) & lmultCoset M = lmultCoset (M,1) ) by Th71, Th72, Th73, Th74; hence Pre-L-Space M = Pre-Lp-Space (M,1) by A1, Def11; ::_thesis: verum end; theorem Th76: :: LPSPACE2:76 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds L-1-Norm M = Lp-Norm (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds L-1-Norm M = Lp-Norm (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds L-1-Norm M = Lp-Norm (M,1) let M be sigma_Measure of S; ::_thesis: L-1-Norm M = Lp-Norm (M,1) A1: the carrier of (Pre-L-Space M) = the carrier of (Pre-Lp-Space (M,1)) by Th75; now__::_thesis:_for_x_being_Element_of_the_carrier_of_(Pre-L-Space_M)_holds_(L-1-Norm_M)_._x_=_(Lp-Norm_(M,1))_._x let x be Element of the carrier of (Pre-L-Space M); ::_thesis: (L-1-Norm M) . x = (Lp-Norm (M,1)) . x x in the carrier of (Pre-L-Space M) ; then x in CosetSet M by LPSPACE1:def_18; then consider g being PartFunc of X,REAL such that A2: ( x = a.e-eq-class (g,M) & g in L1_Functions M ) ; consider a being PartFunc of X,REAL such that A3: ( a in x & (L-1-Norm M) . x = Integral (M,(abs a)) ) by LPSPACE1:def_19; A4: ex p being PartFunc of X,REAL st ( a = p & p in L1_Functions M & g in L1_Functions M & g a.e.= p,M ) by A2, A3; consider b being PartFunc of X,REAL such that A5: ( b in x & ex r being Real st ( r = Integral (M,((abs b) to_power 1)) & (Lp-Norm (M,1)) . x = r to_power (1 / 1) ) ) by A1, Def12; A6: ex q being PartFunc of X,REAL st ( b = q & q in L1_Functions M & g in L1_Functions M & g a.e.= q,M ) by A2, A5; a a.e.= g,M by A4, LPSPACE1:29; then a a.e.= b,M by A6, LPSPACE1:30; then A7: Integral (M,(abs a)) = Integral (M,(abs b)) by A2, A3, A5, LPSPACE1:45; (abs b) to_power 1 = abs b by Th8; hence (L-1-Norm M) . x = (Lp-Norm (M,1)) . x by A3, A5, A7, POWER:25; ::_thesis: verum end; hence L-1-Norm M = Lp-Norm (M,1) by A1, FUNCT_2:63; ::_thesis: verum end; theorem :: LPSPACE2:77 for X being non empty set for S being SigmaField of X for M being sigma_Measure of S holds L-1-Space M = Lp-Space (M,1) proof let X be non empty set ; ::_thesis: for S being SigmaField of X for M being sigma_Measure of S holds L-1-Space M = Lp-Space (M,1) let S be SigmaField of X; ::_thesis: for M being sigma_Measure of S holds L-1-Space M = Lp-Space (M,1) let M be sigma_Measure of S; ::_thesis: L-1-Space M = Lp-Space (M,1) Pre-L-Space M = Pre-Lp-Space (M,1) by Th75; hence L-1-Space M = Lp-Space (M,1) by Th76; ::_thesis: verum end;