:: MIDSP_3 semantic presentation begin theorem :: MIDSP_3:1 for j, k being Element of NAT for D being non empty set for p being FinSequence of D st len p = (j + 1) + k holds ex q, r being FinSequence of D ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) proof let j, k be Element of NAT ; ::_thesis: for D being non empty set for p being FinSequence of D st len p = (j + 1) + k holds ex q, r being FinSequence of D ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) let D be non empty set ; ::_thesis: for p being FinSequence of D st len p = (j + 1) + k holds ex q, r being FinSequence of D ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) let p be FinSequence of D; ::_thesis: ( len p = (j + 1) + k implies ex q, r being FinSequence of D ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) ) assume len p = (j + 1) + k ; ::_thesis: ex q, r being FinSequence of D ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) then consider q9, r being FinSequence of D such that A1: len q9 = j + 1 and A2: ( len r = k & p = q9 ^ r ) by FINSEQ_2:23; consider q being FinSequence of D, c being Element of D such that A3: q9 = q ^ <*c*> by A1, FINSEQ_2:19; take q ; ::_thesis: ex r being FinSequence of D ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) take r ; ::_thesis: ex c being Element of D st ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) take c ; ::_thesis: ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) len q9 = (len q) + 1 by A3, FINSEQ_2:16; hence ( len q = j & len r = k & p = (q ^ <*c*>) ^ r ) by A1, A2, A3; ::_thesis: verum end; theorem :: MIDSP_3:2 for i, n being Element of NAT st i in Seg n holds ex j, k being Element of NAT st ( n = (j + 1) + k & i = j + 1 ) proof let i, n be Element of NAT ; ::_thesis: ( i in Seg n implies ex j, k being Element of NAT st ( n = (j + 1) + k & i = j + 1 ) ) assume A1: i in Seg n ; ::_thesis: ex j, k being Element of NAT st ( n = (j + 1) + k & i = j + 1 ) then 1 <= i by FINSEQ_1:1; then consider j being Nat such that A2: i = 1 + j by NAT_1:10; reconsider j = j as Element of NAT by ORDINAL1:def_12; i <= n by A1, FINSEQ_1:1; then consider k being Nat such that A3: n = (j + 1) + k by A2, NAT_1:10; reconsider k = k as Element of NAT by ORDINAL1:def_12; take j ; ::_thesis: ex k being Element of NAT st ( n = (j + 1) + k & i = j + 1 ) take k ; ::_thesis: ( n = (j + 1) + k & i = j + 1 ) thus ( n = (j + 1) + k & i = j + 1 ) by A2, A3; ::_thesis: verum end; theorem :: MIDSP_3:3 for i being Element of NAT for D being non empty set for c being Element of D for p, q, r being FinSequence of D st p = (q ^ <*c*>) ^ r & i = (len q) + 1 holds ( ( for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ) & p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) proof let i be Element of NAT ; ::_thesis: for D being non empty set for c being Element of D for p, q, r being FinSequence of D st p = (q ^ <*c*>) ^ r & i = (len q) + 1 holds ( ( for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ) & p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) let D be non empty set ; ::_thesis: for c being Element of D for p, q, r being FinSequence of D st p = (q ^ <*c*>) ^ r & i = (len q) + 1 holds ( ( for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ) & p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) let c be Element of D; ::_thesis: for p, q, r being FinSequence of D st p = (q ^ <*c*>) ^ r & i = (len q) + 1 holds ( ( for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ) & p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) let p, q, r be FinSequence of D; ::_thesis: ( p = (q ^ <*c*>) ^ r & i = (len q) + 1 implies ( ( for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ) & p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) ) set q9 = q ^ <*c*>; assume that A1: p = (q ^ <*c*>) ^ r and A2: i = (len q) + 1 ; ::_thesis: ( ( for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ) & p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) A3: p = q ^ (<*c*> ^ r) by A1, FINSEQ_1:32; thus for l being Element of NAT st 1 <= l & l <= len q holds p . l = q . l ::_thesis: ( p . i = c & ( for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) ) ) proof let l be Element of NAT ; ::_thesis: ( 1 <= l & l <= len q implies p . l = q . l ) assume ( 1 <= l & l <= len q ) ; ::_thesis: p . l = q . l then l in dom q by FINSEQ_3:25; hence p . l = q . l by A3, FINSEQ_1:def_7; ::_thesis: verum end; A4: len (q ^ <*c*>) = i by A2, FINSEQ_2:16; i in Seg i by A2, FINSEQ_1:3; then i in dom (q ^ <*c*>) by A4, FINSEQ_1:def_3; hence p . i = (q ^ <*c*>) . i by A1, FINSEQ_1:def_7 .= c by A2, FINSEQ_1:42 ; ::_thesis: for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) len p = (len (q ^ <*c*>)) + (len r) by A1, FINSEQ_1:22; hence for l being Element of NAT st i + 1 <= l & l <= len p holds p . l = r . (l - i) by A1, A4, FINSEQ_1:23; ::_thesis: verum end; theorem Th4: :: MIDSP_3:4 for l, j being Element of NAT holds ( l <= j or l = j + 1 or j + 2 <= l ) proof let l, j be Element of NAT ; ::_thesis: ( l <= j or l = j + 1 or j + 2 <= l ) A1: (j + 1) + 1 = j + 2 ; ( l < j + 1 or l = j + 1 or j + 1 < l ) by XXREAL_0:1; hence ( l <= j or l = j + 1 or j + 2 <= l ) by A1, NAT_1:13; ::_thesis: verum end; theorem :: MIDSP_3:5 for l, n, i, j being Element of NAT st l in (Seg n) \ {i} & i = j + 1 & not ( 1 <= l & l <= j ) holds ( i + 1 <= l & l <= n ) proof let l, n, i, j be Element of NAT ; ::_thesis: ( l in (Seg n) \ {i} & i = j + 1 & not ( 1 <= l & l <= j ) implies ( i + 1 <= l & l <= n ) ) assume that A1: l in (Seg n) \ {i} and A2: i = j + 1 ; ::_thesis: ( ( 1 <= l & l <= j ) or ( i + 1 <= l & l <= n ) ) A3: i + 1 = j + 2 by A2; ( l in Seg n & l <> i ) by A1, ZFMISC_1:56; hence ( ( 1 <= l & l <= j ) or ( i + 1 <= l & l <= n ) ) by A2, A3, Th4, FINSEQ_1:1; ::_thesis: verum end; definition let D be non empty set ; let n be Element of NAT ; let p be Element of n -tuples_on D; let i be Element of NAT ; let d be Element of D; :: original: +* redefine funcp +* (i,d) -> Element of n -tuples_on D; coherence p +* (i,d) is Element of n -tuples_on D proof dom (p +* (i,d)) = dom p by FUNCT_7:30; then len (p +* (i,d)) = len p by FINSEQ_3:29 .= n by CARD_1:def_7 ; hence p +* (i,d) is Element of n -tuples_on D by FINSEQ_2:92; ::_thesis: verum end; end; Lm1: for n, i being Element of NAT for D being non empty set for d being Element of D for p being Element of n -tuples_on D st i in Seg n holds (p +* (i,d)) . i = d proof let n, i be Element of NAT ; ::_thesis: for D being non empty set for d being Element of D for p being Element of n -tuples_on D st i in Seg n holds (p +* (i,d)) . i = d let D be non empty set ; ::_thesis: for d being Element of D for p being Element of n -tuples_on D st i in Seg n holds (p +* (i,d)) . i = d let d be Element of D; ::_thesis: for p being Element of n -tuples_on D st i in Seg n holds (p +* (i,d)) . i = d let p be Element of n -tuples_on D; ::_thesis: ( i in Seg n implies (p +* (i,d)) . i = d ) Seg n = dom p by FINSEQ_2:124; hence ( i in Seg n implies (p +* (i,d)) . i = d ) by FUNCT_7:31; ::_thesis: verum end; Lm2: for n, i being Element of NAT for D being non empty set for d being Element of D for p being Element of n -tuples_on D for l being Element of NAT st l in (dom p) \ {i} holds (p +* (i,d)) . l = p . l proof let n, i be Element of NAT ; ::_thesis: for D being non empty set for d being Element of D for p being Element of n -tuples_on D for l being Element of NAT st l in (dom p) \ {i} holds (p +* (i,d)) . l = p . l let D be non empty set ; ::_thesis: for d being Element of D for p being Element of n -tuples_on D for l being Element of NAT st l in (dom p) \ {i} holds (p +* (i,d)) . l = p . l let d be Element of D; ::_thesis: for p being Element of n -tuples_on D for l being Element of NAT st l in (dom p) \ {i} holds (p +* (i,d)) . l = p . l let p be Element of n -tuples_on D; ::_thesis: for l being Element of NAT st l in (dom p) \ {i} holds (p +* (i,d)) . l = p . l let l be Element of NAT ; ::_thesis: ( l in (dom p) \ {i} implies (p +* (i,d)) . l = p . l ) assume l in (dom p) \ {i} ; ::_thesis: (p +* (i,d)) . l = p . l then not l in {i} by XBOOLE_0:def_5; then l <> i by TARSKI:def_1; hence (p +* (i,d)) . l = p . l by FUNCT_7:32; ::_thesis: verum end; begin definition let n be Element of NAT ; attrc2 is strict ; struct ReperAlgebraStr over n -> MidStr ; aggrReperAlgebraStr(# carrier, MIDPOINT, reper #) -> ReperAlgebraStr over n; sel reper c2 -> Function of (n -tuples_on the carrier of c2), the carrier of c2; end; registration let n be Element of NAT ; let A be non empty set ; let m be BinOp of A; let r be Function of (n -tuples_on A),A; cluster ReperAlgebraStr(# A,m,r #) -> non empty ; coherence not ReperAlgebraStr(# A,m,r #) is empty ; end; Lm3: now__::_thesis:_for_n_being_Element_of_NAT_ for_M_being_MidSp for_R_being_Function_of_((n_+_2)_-tuples_on_the_carrier_of_M),_the_carrier_of_M_holds_ReperAlgebraStr(#_the_carrier_of_M,_the_MIDPOINT_of_M,R_#)_is_MidSp-like let n be Element of NAT ; ::_thesis: for M being MidSp for R being Function of ((n + 2) -tuples_on the carrier of M), the carrier of M holds ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) is MidSp-like let M be MidSp; ::_thesis: for R being Function of ((n + 2) -tuples_on the carrier of M), the carrier of M holds ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) is MidSp-like let R be Function of ((n + 2) -tuples_on the carrier of M), the carrier of M; ::_thesis: ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) is MidSp-like set RA = ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #); thus ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) is MidSp-like ::_thesis: verum proof let a, b, c, d be Element of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #); :: according to MIDSP_1:def_3 ::_thesis: ( a @ a = a & a @ b = b @ a & (a @ b) @ (c @ d) = (a @ c) @ (b @ d) & ex b1 being Element of the carrier of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) st b1 @ a = b ) reconsider a9 = a, b9 = b, c9 = c, d9 = d as Element of M ; thus a @ a = a9 @ a9 .= a by MIDSP_1:def_3 ; ::_thesis: ( a @ b = b @ a & (a @ b) @ (c @ d) = (a @ c) @ (b @ d) & ex b1 being Element of the carrier of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) st b1 @ a = b ) consider x9 being Element of M such that A1: x9 @ a9 = b9 by MIDSP_1:def_3; for a, b being Element of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) for a9, b9 being Element of M st a = a9 & b = b9 holds a @ b = a9 @ b9 ; hence a @ b = b9 @ a9 .= b @ a ; ::_thesis: ( (a @ b) @ (c @ d) = (a @ c) @ (b @ d) & ex b1 being Element of the carrier of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) st b1 @ a = b ) reconsider x = x9 as Element of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) ; thus (a @ b) @ (c @ d) = (a9 @ b9) @ (c9 @ d9) .= (a9 @ c9) @ (b9 @ d9) by MIDSP_1:def_3 .= (a @ c) @ (b @ d) ; ::_thesis: ex b1 being Element of the carrier of ReperAlgebraStr(# the carrier of M, the MIDPOINT of M,R #) st b1 @ a = b take x ; ::_thesis: x @ a = b thus x @ a = b by A1; ::_thesis: verum end; end; registration let n be Element of NAT ; cluster non empty for ReperAlgebraStr over n; existence not for b1 being ReperAlgebraStr over n holds b1 is empty proof set A = the non empty set ; set m = the BinOp of the non empty set ; set r = the Function of (n -tuples_on the non empty set ), the non empty set ; take ReperAlgebraStr(# the non empty set , the BinOp of the non empty set , the Function of (n -tuples_on the non empty set ), the non empty set #) ; ::_thesis: not ReperAlgebraStr(# the non empty set , the BinOp of the non empty set , the Function of (n -tuples_on the non empty set ), the non empty set #) is empty thus not ReperAlgebraStr(# the non empty set , the BinOp of the non empty set , the Function of (n -tuples_on the non empty set ), the non empty set #) is empty ; ::_thesis: verum end; end; registration let n be Element of NAT ; cluster non empty MidSp-like for ReperAlgebraStr over n + 2; existence ex b1 being non empty ReperAlgebraStr over n + 2 st b1 is MidSp-like proof set M = the MidSp; set R = the Function of ((n + 2) -tuples_on the carrier of the MidSp), the carrier of the MidSp; take ReperAlgebraStr(# the carrier of the MidSp, the MIDPOINT of the MidSp, the Function of ((n + 2) -tuples_on the carrier of the MidSp), the carrier of the MidSp #) ; ::_thesis: ReperAlgebraStr(# the carrier of the MidSp, the MIDPOINT of the MidSp, the Function of ((n + 2) -tuples_on the carrier of the MidSp), the carrier of the MidSp #) is MidSp-like thus ReperAlgebraStr(# the carrier of the MidSp, the MIDPOINT of the MidSp, the Function of ((n + 2) -tuples_on the carrier of the MidSp), the carrier of the MidSp #) is MidSp-like by Lm3; ::_thesis: verum end; end; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let i be Element of NAT ; mode Tuple of i,RAS is Element of i -tuples_on the carrier of RAS; end; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let a be Point of RAS; :: original: <* redefine func<*a*> -> Tuple of 1,RAS; coherence <*a*> is Tuple of 1,RAS by FINSEQ_2:98; end; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let i, j be Element of NAT ; let p be Tuple of i,RAS; let q be Tuple of j,RAS; :: original: ^ redefine funcp ^ q -> Tuple of (i + j),RAS; coherence p ^ q is Tuple of (i + j),RAS proof reconsider p = p as Tuple of i, the carrier of RAS ; reconsider q = q as Tuple of j, the carrier of RAS ; p ^ q is Tuple of i + j, the carrier of RAS by FINSEQ_2:107; hence p ^ q is Tuple of (i + j),RAS by FINSEQ_2:131; ::_thesis: verum end; end; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let a be Point of RAS; let p be Tuple of (n + 1),RAS; func *' (a,p) -> Point of RAS equals :: MIDSP_3:def 1 the reper of RAS . (<*a*> ^ p); coherence the reper of RAS . (<*a*> ^ p) is Point of RAS proof reconsider p9 = <*a*> ^ p as Tuple of (n + 2),RAS ; the reper of RAS . p9 is Point of RAS ; hence the reper of RAS . (<*a*> ^ p) is Point of RAS ; ::_thesis: verum end; end; :: deftheorem defines *' MIDSP_3:def_1_:_ for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a being Point of RAS for p being Tuple of (n + 1),RAS holds *' (a,p) = the reper of RAS . (<*a*> ^ p); theorem :: MIDSP_3:6 for i, n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for d being Point of RAS for p being Tuple of (n + 1),RAS st i in Seg (n + 1) holds ( (p +* (i,d)) . i = d & ( for l being Element of NAT st l in (dom p) \ {i} holds (p +* (i,d)) . l = p . l ) ) by Lm1, Lm2; definition let n be Element of NAT ; mode Nat of n -> Element of NAT means :Def2: :: MIDSP_3:def 2 ( 1 <= it & it <= n + 1 ); existence ex b1 being Element of NAT st ( 1 <= b1 & b1 <= n + 1 ) proof take 1 ; ::_thesis: ( 1 <= 1 & 1 <= n + 1 ) 0 <= n by NAT_1:2; then 0 + 1 <= n + 1 by XREAL_1:7; hence ( 1 <= 1 & 1 <= n + 1 ) ; ::_thesis: verum end; end; :: deftheorem Def2 defines Nat MIDSP_3:def_2_:_ for n, b2 being Element of NAT holds ( b2 is Nat of n iff ( 1 <= b2 & b2 <= n + 1 ) ); theorem Th7: :: MIDSP_3:7 for i, n being Element of NAT holds ( i is Nat of n iff i in Seg (n + 1) ) proof let i, n be Element of NAT ; ::_thesis: ( i is Nat of n iff i in Seg (n + 1) ) ( i is Nat of n iff ( 1 <= i & i <= n + 1 ) ) by Def2; hence ( i is Nat of n iff i in Seg (n + 1) ) by FINSEQ_1:1; ::_thesis: verum end; theorem Th8: :: MIDSP_3:8 for i, n being Element of NAT st i <= n holds i + 1 is Nat of n proof let i, n be Element of NAT ; ::_thesis: ( i <= n implies i + 1 is Nat of n ) assume i <= n ; ::_thesis: i + 1 is Nat of n then A1: i + 1 <= n + 1 by XREAL_1:7; 1 <= i + 1 by NAT_1:11; hence i + 1 is Nat of n by A1, Def2; ::_thesis: verum end; theorem Th9: :: MIDSP_3:9 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds p . m = q . m ) holds p = q proof let n be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds p . m = q . m ) holds p = q let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds p . m = q . m ) holds p = q let p, q be Tuple of (n + 1),RAS; ::_thesis: ( ( for m being Nat of n holds p . m = q . m ) implies p = q ) assume A1: for m being Nat of n holds p . m = q . m ; ::_thesis: p = q for j being Nat st j in Seg (n + 1) holds p . j = q . j proof let j be Nat; ::_thesis: ( j in Seg (n + 1) implies p . j = q . j ) assume j in Seg (n + 1) ; ::_thesis: p . j = q . j then reconsider j = j as Nat of n by Th7; p . j = q . j by A1; hence p . j = q . j ; ::_thesis: verum end; hence p = q by FINSEQ_2:119; ::_thesis: verum end; theorem Th10: :: MIDSP_3:10 for n, i being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for d being Point of RAS for p being Tuple of (n + 1),RAS for l being Nat of n st l = i holds (p +* (i,d)) . l = d proof let n, i be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for d being Point of RAS for p being Tuple of (n + 1),RAS for l being Nat of n st l = i holds (p +* (i,d)) . l = d let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for d being Point of RAS for p being Tuple of (n + 1),RAS for l being Nat of n st l = i holds (p +* (i,d)) . l = d let d be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for l being Nat of n st l = i holds (p +* (i,d)) . l = d let p be Tuple of (n + 1),RAS; ::_thesis: for l being Nat of n st l = i holds (p +* (i,d)) . l = d let l be Nat of n; ::_thesis: ( l = i implies (p +* (i,d)) . l = d ) assume A1: l = i ; ::_thesis: (p +* (i,d)) . l = d l in Seg (n + 1) by Th7; hence (p +* (i,d)) . l = d by A1, Lm1; ::_thesis: verum end; definition let n be Element of NAT ; let D be non empty set ; let p be Element of (n + 1) -tuples_on D; let m be Nat of n; :: original: . redefine funcp . m -> Element of D; coherence p . m is Element of D proof reconsider S = Seg (n + 1) as non empty set by FINSEQ_1:4; ( m in S & len p = n + 1 ) by Th7, CARD_1:def_7; then m in dom p by FINSEQ_1:def_3; then ( rng p c= D & p . m in rng p ) by FINSEQ_1:def_4, FUNCT_1:def_3; hence p . m is Element of D ; ::_thesis: verum end; end; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; attrRAS is being_invariance means :Def3: :: MIDSP_3:def 3 for a, b being Point of RAS for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) holds a @ (*' (b,q)) = b @ (*' (a,p)); end; :: deftheorem Def3 defines being_invariance MIDSP_3:def_3_:_ for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 holds ( RAS is being_invariance iff for a, b being Point of RAS for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) holds a @ (*' (b,q)) = b @ (*' (a,p)) ); definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let p be Tuple of (n + 1),RAS; let i be Element of NAT ; let a be Point of RAS; :: original: +* redefine funcp +* (i,a) -> Tuple of (n + 1),RAS; coherence p +* (i,a) is Tuple of (n + 1),RAS proof thus p +* (i,a) is Tuple of (n + 1),RAS ; ::_thesis: verum end; end; definition let n, i be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; predRAS has_property_of_zero_in i means :Def4: :: MIDSP_3:def 4 for a being Point of RAS for p being Tuple of (n + 1),RAS holds *' (a,(p +* (i,a))) = a; end; :: deftheorem Def4 defines has_property_of_zero_in MIDSP_3:def_4_:_ for n, i being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 holds ( RAS has_property_of_zero_in i iff for a being Point of RAS for p being Tuple of (n + 1),RAS holds *' (a,(p +* (i,a))) = a ); definition let n, i be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; predRAS is_semi_additive_in i means :Def5: :: MIDSP_3:def 5 for a, pii being Point of RAS for p being Tuple of (n + 1),RAS st p . i = pii holds *' (a,(p +* (i,(a @ pii)))) = a @ (*' (a,p)); end; :: deftheorem Def5 defines is_semi_additive_in MIDSP_3:def_5_:_ for n, i being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 holds ( RAS is_semi_additive_in i iff for a, pii being Point of RAS for p being Tuple of (n + 1),RAS st p . i = pii holds *' (a,(p +* (i,(a @ pii)))) = a @ (*' (a,p)) ); theorem Th11: :: MIDSP_3:11 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for m being Nat of n st RAS is_semi_additive_in m holds for a, d being Point of RAS for p, q being Tuple of (n + 1),RAS st q = p +* (m,d) holds *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) proof let n be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for m being Nat of n st RAS is_semi_additive_in m holds for a, d being Point of RAS for p, q being Tuple of (n + 1),RAS st q = p +* (m,d) holds *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for m being Nat of n st RAS is_semi_additive_in m holds for a, d being Point of RAS for p, q being Tuple of (n + 1),RAS st q = p +* (m,d) holds *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) let m be Nat of n; ::_thesis: ( RAS is_semi_additive_in m implies for a, d being Point of RAS for p, q being Tuple of (n + 1),RAS st q = p +* (m,d) holds *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) ) assume A1: RAS is_semi_additive_in m ; ::_thesis: for a, d being Point of RAS for p, q being Tuple of (n + 1),RAS st q = p +* (m,d) holds *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) let a, d be Point of RAS; ::_thesis: for p, q being Tuple of (n + 1),RAS st q = p +* (m,d) holds *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) let p, q be Tuple of (n + 1),RAS; ::_thesis: ( q = p +* (m,d) implies *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) ) set qq = q +* (m,(a @ d)); assume A2: q = p +* (m,d) ; ::_thesis: *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) A3: q +* (m,(a @ d)) = p +* (m,(a @ d)) proof set pp = p +* (m,(a @ d)); for k being Nat of n holds (q +* (m,(a @ d))) . k = (p +* (m,(a @ d))) . k proof let k be Nat of n; ::_thesis: (q +* (m,(a @ d))) . k = (p +* (m,(a @ d))) . k now__::_thesis:_(q_+*_(m,(a_@_d)))_._k_=_(p_+*_(m,(a_@_d)))_._k percases ( k = m or k <> m ) ; supposeA4: k = m ; ::_thesis: (q +* (m,(a @ d))) . k = (p +* (m,(a @ d))) . k (p +* (m,(a @ d))) . m = a @ d by Th10; hence (q +* (m,(a @ d))) . k = (p +* (m,(a @ d))) . k by A4, Th10; ::_thesis: verum end; supposeA5: k <> m ; ::_thesis: (q +* (m,(a @ d))) . k = (p +* (m,(a @ d))) . k hence (q +* (m,(a @ d))) . k = q . k by FUNCT_7:32 .= p . k by A2, A5, FUNCT_7:32 .= (p +* (m,(a @ d))) . k by A5, FUNCT_7:32 ; ::_thesis: verum end; end; end; hence (q +* (m,(a @ d))) . k = (p +* (m,(a @ d))) . k ; ::_thesis: verum end; hence q +* (m,(a @ d)) = p +* (m,(a @ d)) by Th9; ::_thesis: verum end; q . m = d by A2, Th10; hence *' (a,(p +* (m,(a @ d)))) = a @ (*' (a,q)) by A1, A3, Def5; ::_thesis: verum end; definition let n, i be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; predRAS is_additive_in i means :Def6: :: MIDSP_3:def 6 for a, pii, p9i being Point of RAS for p being Tuple of (n + 1),RAS st p . i = pii holds *' (a,(p +* (i,(pii @ p9i)))) = (*' (a,p)) @ (*' (a,(p +* (i,p9i)))); end; :: deftheorem Def6 defines is_additive_in MIDSP_3:def_6_:_ for n, i being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 holds ( RAS is_additive_in i iff for a, pii, p9i being Point of RAS for p being Tuple of (n + 1),RAS st p . i = pii holds *' (a,(p +* (i,(pii @ p9i)))) = (*' (a,p)) @ (*' (a,(p +* (i,p9i)))) ); definition let n, i be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; predRAS is_alternative_in i means :Def7: :: MIDSP_3:def 7 for a being Point of RAS for p being Tuple of (n + 1),RAS for pii being Point of RAS st p . i = pii holds *' (a,(p +* ((i + 1),pii))) = a; end; :: deftheorem Def7 defines is_alternative_in MIDSP_3:def_7_:_ for n, i being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 holds ( RAS is_alternative_in i iff for a being Point of RAS for p being Tuple of (n + 1),RAS for pii being Point of RAS st p . i = pii holds *' (a,(p +* ((i + 1),pii))) = a ); definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let W be ATLAS of RAS; let i be Element of NAT ; mode Tuple of i,W is Element of i -tuples_on the carrier of the algebra of W; end; theorem :: MIDSP_3:12 for i, n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st i in Seg (n + 1) holds ( (x +* (i,v)) . i = v & ( for l being Element of NAT st l in (dom x) \ {i} holds (x +* (i,v)) . l = x . l ) ) by Lm1, Lm2; theorem Th13: :: MIDSP_3:13 for n, i being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W holds ( ( for l being Nat of n st l = i holds (x +* (i,v)) . l = v ) & ( for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l ) ) proof let n, i be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W holds ( ( for l being Nat of n st l = i holds (x +* (i,v)) . l = v ) & ( for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l ) ) let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W holds ( ( for l being Nat of n st l = i holds (x +* (i,v)) . l = v ) & ( for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l ) ) let W be ATLAS of RAS; ::_thesis: for v being Vector of W for x being Tuple of (n + 1),W holds ( ( for l being Nat of n st l = i holds (x +* (i,v)) . l = v ) & ( for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l ) ) let v be Vector of W; ::_thesis: for x being Tuple of (n + 1),W holds ( ( for l being Nat of n st l = i holds (x +* (i,v)) . l = v ) & ( for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l ) ) let x be Tuple of (n + 1),W; ::_thesis: ( ( for l being Nat of n st l = i holds (x +* (i,v)) . l = v ) & ( for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l ) ) thus for l being Nat of n st l = i holds (x +* (i,v)) . l = v ::_thesis: for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l proof let l be Nat of n; ::_thesis: ( l = i implies (x +* (i,v)) . l = v ) assume A1: l = i ; ::_thesis: (x +* (i,v)) . l = v l in Seg (n + 1) by Th7; hence (x +* (i,v)) . l = v by A1, Lm1; ::_thesis: verum end; thus for l, i being Nat of n st l <> i holds (x +* (i,v)) . l = x . l by FUNCT_7:32; ::_thesis: verum end; theorem Th14: :: MIDSP_3:14 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for x, y being Tuple of (n + 1),W st ( for m being Nat of n holds x . m = y . m ) holds x = y proof let n be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for x, y being Tuple of (n + 1),W st ( for m being Nat of n holds x . m = y . m ) holds x = y let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for W being ATLAS of RAS for x, y being Tuple of (n + 1),W st ( for m being Nat of n holds x . m = y . m ) holds x = y let W be ATLAS of RAS; ::_thesis: for x, y being Tuple of (n + 1),W st ( for m being Nat of n holds x . m = y . m ) holds x = y let x, y be Tuple of (n + 1),W; ::_thesis: ( ( for m being Nat of n holds x . m = y . m ) implies x = y ) assume A1: for m being Nat of n holds x . m = y . m ; ::_thesis: x = y for j being Nat st j in Seg (n + 1) holds x . j = y . j proof let j be Nat; ::_thesis: ( j in Seg (n + 1) implies x . j = y . j ) assume j in Seg (n + 1) ; ::_thesis: x . j = y . j then reconsider j = j as Nat of n by Th7; x . j = y . j by A1; hence x . j = y . j ; ::_thesis: verum end; hence x = y by FINSEQ_2:119; ::_thesis: verum end; scheme :: MIDSP_3:sch 1 SeqLambdaD9{ F1() -> Element of NAT , F2() -> non empty set , F3( set ) -> Element of F2() } : ex z being FinSequence of F2() st ( len z = F1() + 1 & ( for j being Nat of F1() holds z . j = F3(j) ) ) proof reconsider S = Seg (F1() + 1) as non empty set by FINSEQ_1:4; consider z being FinSequence of F2() such that A1: len z = F1() + 1 and A2: for j being Nat st j in dom z holds z . j = F3(j) from FINSEQ_2:sch_1(); take z ; ::_thesis: ( len z = F1() + 1 & ( for j being Nat of F1() holds z . j = F3(j) ) ) A3: dom z = Seg (F1() + 1) by A1, FINSEQ_1:def_3; for j being Nat of F1() holds z . j = F3(j) proof let j be Nat of F1(); ::_thesis: z . j = F3(j) j in S by Th7; hence z . j = F3(j) by A2, A3; ::_thesis: verum end; hence ( len z = F1() + 1 & ( for j being Nat of F1() holds z . j = F3(j) ) ) by A1; ::_thesis: verum end; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let W be ATLAS of RAS; let a be Point of RAS; let x be Tuple of (n + 1),W; func(a,x) . W -> Tuple of (n + 1),RAS means :Def8: :: MIDSP_3:def 8 for m being Nat of n holds it . m = (a,(x . m)) . W; existence ex b1 being Tuple of (n + 1),RAS st for m being Nat of n holds b1 . m = (a,(x . m)) . W proof deffunc H1( Nat of n) -> Element of the carrier of RAS = (a,(x . $1)) . W; consider z being FinSequence of the carrier of RAS such that A1: len z = n + 1 and A2: for m being Nat of n holds z . m = H1(m) from MIDSP_3:sch_1(); reconsider z = z as Tuple of (n + 1),RAS by A1, FINSEQ_2:92; take z ; ::_thesis: for m being Nat of n holds z . m = (a,(x . m)) . W thus for m being Nat of n holds z . m = (a,(x . m)) . W by A2; ::_thesis: verum end; uniqueness for b1, b2 being Tuple of (n + 1),RAS st ( for m being Nat of n holds b1 . m = (a,(x . m)) . W ) & ( for m being Nat of n holds b2 . m = (a,(x . m)) . W ) holds b1 = b2 proof let p, q be Tuple of (n + 1),RAS; ::_thesis: ( ( for m being Nat of n holds p . m = (a,(x . m)) . W ) & ( for m being Nat of n holds q . m = (a,(x . m)) . W ) implies p = q ) assume that A3: for m being Nat of n holds p . m = (a,(x . m)) . W and A4: for m being Nat of n holds q . m = (a,(x . m)) . W ; ::_thesis: p = q for m being Nat of n holds p . m = q . m proof let m be Nat of n; ::_thesis: p . m = q . m p . m = (a,(x . m)) . W by A3; hence p . m = q . m by A4; ::_thesis: verum end; hence p = q by Th9; ::_thesis: verum end; end; :: deftheorem Def8 defines . MIDSP_3:def_8_:_ for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for a being Point of RAS for x being Tuple of (n + 1),W for b6 being Tuple of (n + 1),RAS holds ( b6 = (a,x) . W iff for m being Nat of n holds b6 . m = (a,(x . m)) . W ); definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let W be ATLAS of RAS; let a be Point of RAS; let p be Tuple of (n + 1),RAS; funcW . (a,p) -> Tuple of (n + 1),W means :Def9: :: MIDSP_3:def 9 for m being Nat of n holds it . m = W . (a,(p . m)); existence ex b1 being Tuple of (n + 1),W st for m being Nat of n holds b1 . m = W . (a,(p . m)) proof deffunc H1( Nat of n) -> Element of the carrier of the algebra of W = W . (a,(p . $1)); consider z being FinSequence of the carrier of the algebra of W such that A1: len z = n + 1 and A2: for m being Nat of n holds z . m = H1(m) from MIDSP_3:sch_1(); reconsider z = z as Tuple of (n + 1),W by A1, FINSEQ_2:92; take z ; ::_thesis: for m being Nat of n holds z . m = W . (a,(p . m)) thus for m being Nat of n holds z . m = W . (a,(p . m)) by A2; ::_thesis: verum end; uniqueness for b1, b2 being Tuple of (n + 1),W st ( for m being Nat of n holds b1 . m = W . (a,(p . m)) ) & ( for m being Nat of n holds b2 . m = W . (a,(p . m)) ) holds b1 = b2 proof let x, y be Tuple of (n + 1),W; ::_thesis: ( ( for m being Nat of n holds x . m = W . (a,(p . m)) ) & ( for m being Nat of n holds y . m = W . (a,(p . m)) ) implies x = y ) assume that A3: for m being Nat of n holds x . m = W . (a,(p . m)) and A4: for m being Nat of n holds y . m = W . (a,(p . m)) ; ::_thesis: x = y for m being Nat of n holds x . m = y . m proof let m be Nat of n; ::_thesis: x . m = y . m W . (a,(p . m)) = x . m by A3; hence x . m = y . m by A4; ::_thesis: verum end; hence x = y by Th14; ::_thesis: verum end; end; :: deftheorem Def9 defines . MIDSP_3:def_9_:_ for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for a being Point of RAS for p being Tuple of (n + 1),RAS for b6 being Tuple of (n + 1),W holds ( b6 = W . (a,p) iff for m being Nat of n holds b6 . m = W . (a,(p . m)) ); theorem Th15: :: MIDSP_3:15 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds ( W . (a,p) = x iff (a,x) . W = p ) proof let n be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds ( W . (a,p) = x iff (a,x) . W = p ) let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds ( W . (a,p) = x iff (a,x) . W = p ) let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds ( W . (a,p) = x iff (a,x) . W = p ) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for x being Tuple of (n + 1),W holds ( W . (a,p) = x iff (a,x) . W = p ) let W be ATLAS of RAS; ::_thesis: for x being Tuple of (n + 1),W holds ( W . (a,p) = x iff (a,x) . W = p ) let x be Tuple of (n + 1),W; ::_thesis: ( W . (a,p) = x iff (a,x) . W = p ) thus ( W . (a,p) = x implies (a,x) . W = p ) ::_thesis: ( (a,x) . W = p implies W . (a,p) = x ) proof assume A1: W . (a,p) = x ; ::_thesis: (a,x) . W = p now__::_thesis:_for_m_being_Nat_of_n_holds_(a,(x_._m))_._W_=_p_._m let m be Nat of n; ::_thesis: (a,(x . m)) . W = p . m W . (a,(p . m)) = x . m by A1, Def9; hence (a,(x . m)) . W = p . m by MIDSP_2:33; ::_thesis: verum end; hence (a,x) . W = p by Def8; ::_thesis: verum end; thus ( (a,x) . W = p implies W . (a,p) = x ) ::_thesis: verum proof assume A2: (a,x) . W = p ; ::_thesis: W . (a,p) = x now__::_thesis:_for_m_being_Nat_of_n_holds_W_._(a,(p_._m))_=_x_._m let m be Nat of n; ::_thesis: W . (a,(p . m)) = x . m (a,(x . m)) . W = p . m by A2, Def8; hence W . (a,(p . m)) = x . m by MIDSP_2:33; ::_thesis: verum end; hence W . (a,p) = x by Def9; ::_thesis: verum end; end; theorem :: MIDSP_3:16 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a being Point of RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds W . (a,((a,x) . W)) = x by Th15; theorem :: MIDSP_3:17 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS holds (a,(W . (a,p))) . W = p by Th15; definition let n be Element of NAT ; let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; let W be ATLAS of RAS; let a be Point of RAS; let x be Tuple of (n + 1),W; func Phi (a,x) -> Vector of W equals :: MIDSP_3:def 10 W . (a,(*' (a,((a,x) . W)))); coherence W . (a,(*' (a,((a,x) . W)))) is Vector of W ; end; :: deftheorem defines Phi MIDSP_3:def_10_:_ for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS for a being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = W . (a,(*' (a,((a,x) . W)))); theorem Th18: :: MIDSP_3:18 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) proof let n be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) let a, b be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) let W be ATLAS of RAS; ::_thesis: for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) let v be Vector of W; ::_thesis: for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds ( *' (a,p) = b iff Phi (a,x) = v ) let x be Tuple of (n + 1),W; ::_thesis: ( W . (a,p) = x & W . (a,b) = v implies ( *' (a,p) = b iff Phi (a,x) = v ) ) assume that A1: W . (a,p) = x and A2: W . (a,b) = v ; ::_thesis: ( *' (a,p) = b iff Phi (a,x) = v ) Phi (a,x) = W . (a,(*' (a,p))) by A1, Th15; hence ( *' (a,p) = b iff Phi (a,x) = v ) by A2, MIDSP_2:32; ::_thesis: verum end; theorem Th19: :: MIDSP_3:19 for n being Element of NAT for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS holds ( RAS is being_invariance iff for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ) proof let n be Element of NAT ; ::_thesis: for RAS being non empty MidSp-like ReperAlgebraStr over n + 2 for W being ATLAS of RAS holds ( RAS is being_invariance iff for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ) let RAS be non empty MidSp-like ReperAlgebraStr over n + 2; ::_thesis: for W being ATLAS of RAS holds ( RAS is being_invariance iff for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ) let W be ATLAS of RAS; ::_thesis: ( RAS is being_invariance iff for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ) A1: ( ( for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ) implies RAS is being_invariance ) proof assume A2: for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ; ::_thesis: RAS is being_invariance let a be Point of RAS; :: according to MIDSP_3:def_3 ::_thesis: for b being Point of RAS for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) holds a @ (*' (b,q)) = b @ (*' (a,p)) let b be Point of RAS; ::_thesis: for p, q being Tuple of (n + 1),RAS st ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) holds a @ (*' (b,q)) = b @ (*' (a,p)) let p, q be Tuple of (n + 1),RAS; ::_thesis: ( ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) implies a @ (*' (b,q)) = b @ (*' (a,p)) ) A3: W . (a,(*' (a,((a,(W . (a,p))) . W)))) = Phi (a,(W . (a,p))) .= Phi (b,(W . (a,p))) by A2 .= W . (b,(*' (b,((b,(W . (a,p))) . W)))) ; assume A4: for m being Nat of n holds a @ (q . m) = b @ (p . m) ; ::_thesis: a @ (*' (b,q)) = b @ (*' (a,p)) A5: now__::_thesis:_for_m_being_Nat_of_n_holds_(W_._(a,p))_._m_=_(W_._(b,q))_._m let m be Nat of n; ::_thesis: (W . (a,p)) . m = (W . (b,q)) . m a @ (q . m) = b @ (p . m) by A4; then A6: W . (a,(p . m)) = W . (b,(q . m)) by MIDSP_2:33; thus (W . (a,p)) . m = W . (a,(p . m)) by Def9 .= (W . (b,q)) . m by A6, Def9 ; ::_thesis: verum end; W . (a,(*' (a,p))) = W . (a,(*' (a,((a,(W . (a,p))) . W)))) by Th15 .= W . (b,(*' (b,((b,(W . (b,q))) . W)))) by A5, A3, Th14 .= W . (b,(*' (b,q))) by Th15 ; hence a @ (*' (b,q)) = b @ (*' (a,p)) by MIDSP_2:33; ::_thesis: verum end; now__::_thesis:_(_RAS_is_being_invariance_implies_for_a,_b_being_Point_of_RAS for_x_being_Tuple_of_(n_+_1),W_holds_Phi_(a,x)_=_Phi_(b,x)_) assume A7: RAS is being_invariance ; ::_thesis: for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) let a, b be Point of RAS; ::_thesis: for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) let x be Tuple of (n + 1),W; ::_thesis: Phi (a,x) = Phi (b,x) set p = (a,x) . W; set q = (b,x) . W; A8: W . (a,((a,x) . W)) = x by Th15 .= W . (b,((b,x) . W)) by Th15 ; now__::_thesis:_for_m_being_Nat_of_n_holds_a_@_(((b,x)_._W)_._m)_=_b_@_(((a,x)_._W)_._m) let m be Nat of n; ::_thesis: a @ (((b,x) . W) . m) = b @ (((a,x) . W) . m) W . (a,(((a,x) . W) . m)) = (W . (a,((a,x) . W))) . m by Def9 .= W . (b,(((b,x) . W) . m)) by A8, Def9 ; hence a @ (((b,x) . W) . m) = b @ (((a,x) . W) . m) by MIDSP_2:33; ::_thesis: verum end; then a @ (*' (b,((b,x) . W))) = b @ (*' (a,((a,x) . W))) by A7, Def3; hence Phi (a,x) = Phi (b,x) by MIDSP_2:33; ::_thesis: verum end; hence ( RAS is being_invariance iff for a, b being Point of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) ) by A1; ::_thesis: verum end; theorem Th20: :: MIDSP_3:20 for n being Element of NAT holds 1 in Seg (n + 1) proof let n be Element of NAT ; ::_thesis: 1 in Seg (n + 1) 0 <= n by NAT_1:2; then 0 + 1 <= n + 1 by XREAL_1:7; hence 1 in Seg (n + 1) by FINSEQ_1:1; ::_thesis: verum end; theorem Th21: :: MIDSP_3:21 for n being Element of NAT holds 1 is Nat of n proof let n be Element of NAT ; ::_thesis: 1 is Nat of n 1 in Seg (n + 1) by Th20; hence 1 is Nat of n by Th7; ::_thesis: verum end; begin definition let n be Element of NAT ; mode ReperAlgebra of n -> non empty MidSp-like ReperAlgebraStr over n + 2 means :Def11: :: MIDSP_3:def 11 it is being_invariance ; existence ex b1 being non empty MidSp-like ReperAlgebraStr over n + 2 st b1 is being_invariance proof reconsider one1 = 1 as Nat of n + 1 by Th21; set M = the MidSp; set D = the carrier of the MidSp; set k = (n + 1) + 1; set C = ((n + 1) + 1) -tuples_on the carrier of the MidSp; deffunc H1( Element of ((n + 1) + 1) -tuples_on the carrier of the MidSp) -> Element of the carrier of the MidSp = $1 . one1; consider R being Function of (((n + 1) + 1) -tuples_on the carrier of the MidSp), the carrier of the MidSp such that A1: for p being Element of ((n + 1) + 1) -tuples_on the carrier of the MidSp holds R . p = H1(p) from FUNCT_2:sch_4(); reconsider R = R as Function of ((n + 2) -tuples_on the carrier of the MidSp), the carrier of the MidSp ; reconsider RA = ReperAlgebraStr(# the carrier of the MidSp, the MIDPOINT of the MidSp,R #) as non empty MidSp-like ReperAlgebraStr over n + 2 by Lm3; take RA ; ::_thesis: RA is being_invariance for a, b being Point of RA for p, q being Tuple of (n + 1),RA st ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) holds a @ (*' (b,q)) = b @ (*' (a,p)) proof let a, b be Point of RA; ::_thesis: for p, q being Tuple of (n + 1),RA st ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) holds a @ (*' (b,q)) = b @ (*' (a,p)) let p, q be Tuple of (n + 1),RA; ::_thesis: ( ( for m being Nat of n holds a @ (q . m) = b @ (p . m) ) implies a @ (*' (b,q)) = b @ (*' (a,p)) ) assume for m being Nat of n holds a @ (q . m) = b @ (p . m) ; ::_thesis: a @ (*' (b,q)) = b @ (*' (a,p)) A2: *' (a,p) = (<*a*> ^ p) . one1 by A1 .= a by FINSEQ_1:41 ; *' (b,q) = (<*b*> ^ q) . one1 by A1 .= b by FINSEQ_1:41 ; hence a @ (*' (b,q)) = b @ (*' (a,p)) by A2; ::_thesis: verum end; hence RA is being_invariance by Def3; ::_thesis: verum end; end; :: deftheorem Def11 defines ReperAlgebra MIDSP_3:def_11_:_ for n being Element of NAT for b2 being non empty MidSp-like ReperAlgebraStr over n + 2 holds ( b2 is ReperAlgebra of n iff b2 is being_invariance ); theorem Th22: :: MIDSP_3:22 for n being Element of NAT for RAS being ReperAlgebra of n for a, b being Point of RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) proof let n be Element of NAT ; ::_thesis: for RAS being ReperAlgebra of n for a, b being Point of RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) let RAS be ReperAlgebra of n; ::_thesis: for a, b being Point of RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) let a, b be Point of RAS; ::_thesis: for W being ATLAS of RAS for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) let W be ATLAS of RAS; ::_thesis: for x being Tuple of (n + 1),W holds Phi (a,x) = Phi (b,x) let x be Tuple of (n + 1),W; ::_thesis: Phi (a,x) = Phi (b,x) RAS is being_invariance by Def11; hence Phi (a,x) = Phi (b,x) by Th19; ::_thesis: verum end; definition let n be Element of NAT ; let RAS be ReperAlgebra of n; let W be ATLAS of RAS; let x be Tuple of (n + 1),W; func Phi x -> Vector of W means :Def12: :: MIDSP_3:def 12 for a being Point of RAS holds it = Phi (a,x); existence ex b1 being Vector of W st for a being Point of RAS holds b1 = Phi (a,x) proof set a = the Point of RAS; take Phi ( the Point of RAS,x) ; ::_thesis: for a being Point of RAS holds Phi ( the Point of RAS,x) = Phi (a,x) thus for a being Point of RAS holds Phi ( the Point of RAS,x) = Phi (a,x) by Th22; ::_thesis: verum end; uniqueness for b1, b2 being Vector of W st ( for a being Point of RAS holds b1 = Phi (a,x) ) & ( for a being Point of RAS holds b2 = Phi (a,x) ) holds b1 = b2 proof set a = the Point of RAS; let y, z be Vector of W; ::_thesis: ( ( for a being Point of RAS holds y = Phi (a,x) ) & ( for a being Point of RAS holds z = Phi (a,x) ) implies y = z ) assume that A1: for a being Point of RAS holds y = Phi (a,x) and A2: for a being Point of RAS holds z = Phi (a,x) ; ::_thesis: y = z y = Phi ( the Point of RAS,x) by A1; hence y = z by A2; ::_thesis: verum end; end; :: deftheorem Def12 defines Phi MIDSP_3:def_12_:_ for n being Element of NAT for RAS being ReperAlgebra of n for W being ATLAS of RAS for x being Tuple of (n + 1),W for b5 being Vector of W holds ( b5 = Phi x iff for a being Point of RAS holds b5 = Phi (a,x) ); Lm4: for n being Element of NAT for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x holds Phi x = W . (a,(*' (a,p))) proof let n be Element of NAT ; ::_thesis: for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x holds Phi x = W . (a,(*' (a,p))) let RAS be ReperAlgebra of n; ::_thesis: for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x holds Phi x = W . (a,(*' (a,p))) let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x holds Phi x = W . (a,(*' (a,p))) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x holds Phi x = W . (a,(*' (a,p))) let W be ATLAS of RAS; ::_thesis: for x being Tuple of (n + 1),W st W . (a,p) = x holds Phi x = W . (a,(*' (a,p))) let x be Tuple of (n + 1),W; ::_thesis: ( W . (a,p) = x implies Phi x = W . (a,(*' (a,p))) ) assume A1: W . (a,p) = x ; ::_thesis: Phi x = W . (a,(*' (a,p))) thus Phi x = Phi (a,x) by Def12 .= W . (a,(*' (a,p))) by A1, Th15 ; ::_thesis: verum end; Lm5: for n being Element of NAT for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p holds Phi x = W . (a,(*' (a,p))) proof let n be Element of NAT ; ::_thesis: for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p holds Phi x = W . (a,(*' (a,p))) let RAS be ReperAlgebra of n; ::_thesis: for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p holds Phi x = W . (a,(*' (a,p))) let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p holds Phi x = W . (a,(*' (a,p))) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p holds Phi x = W . (a,(*' (a,p))) let W be ATLAS of RAS; ::_thesis: for x being Tuple of (n + 1),W st (a,x) . W = p holds Phi x = W . (a,(*' (a,p))) let x be Tuple of (n + 1),W; ::_thesis: ( (a,x) . W = p implies Phi x = W . (a,(*' (a,p))) ) assume (a,x) . W = p ; ::_thesis: Phi x = W . (a,(*' (a,p))) then W . (a,p) = x by Th15; hence Phi x = W . (a,(*' (a,p))) by Lm4; ::_thesis: verum end; theorem Th23: :: MIDSP_3:23 for n being Element of NAT for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b proof let n be Element of NAT ; ::_thesis: for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b let RAS be ReperAlgebra of n; ::_thesis: for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b let a, b be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b let W be ATLAS of RAS; ::_thesis: for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b let v be Vector of W; ::_thesis: for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v & Phi x = v holds *' (a,p) = b let x be Tuple of (n + 1),W; ::_thesis: ( W . (a,p) = x & W . (a,b) = v & Phi x = v implies *' (a,p) = b ) assume A1: ( W . (a,p) = x & W . (a,b) = v & Phi x = v ) ; ::_thesis: *' (a,p) = b Phi x = Phi (a,x) by Def12; hence *' (a,p) = b by A1, Th18; ::_thesis: verum end; theorem Th24: :: MIDSP_3:24 for n being Element of NAT for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v proof let n be Element of NAT ; ::_thesis: for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v let RAS be ReperAlgebra of n; ::_thesis: for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v let a, b be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v let W be ATLAS of RAS; ::_thesis: for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v let v be Vector of W; ::_thesis: for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b & *' (a,p) = b holds Phi x = v let x be Tuple of (n + 1),W; ::_thesis: ( (a,x) . W = p & (a,v) . W = b & *' (a,p) = b implies Phi x = v ) assume ( (a,x) . W = p & (a,v) . W = b & *' (a,p) = b ) ; ::_thesis: Phi x = v then Phi (a,x) = v by MIDSP_2:33; hence Phi x = v by Def12; ::_thesis: verum end; theorem Th25: :: MIDSP_3:25 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let RAS be ReperAlgebra of n; ::_thesis: for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let a, b be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let W be ATLAS of RAS; ::_thesis: for v being Vector of W for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let v be Vector of W; ::_thesis: for x being Tuple of (n + 1),W st W . (a,p) = x & W . (a,b) = v holds W . (a,(p +* (m,b))) = x +* (m,v) let x be Tuple of (n + 1),W; ::_thesis: ( W . (a,p) = x & W . (a,b) = v implies W . (a,(p +* (m,b))) = x +* (m,v) ) assume that A1: W . (a,p) = x and A2: W . (a,b) = v ; ::_thesis: W . (a,(p +* (m,b))) = x +* (m,v) set q = p +* (m,b); set y = W . (a,(p +* (m,b))); set z = x +* (m,v); for k being Nat of n holds (W . (a,(p +* (m,b)))) . k = (x +* (m,v)) . k proof let k be Nat of n; ::_thesis: (W . (a,(p +* (m,b)))) . k = (x +* (m,v)) . k now__::_thesis:_(W_._(a,(p_+*_(m,b))))_._k_=_(x_+*_(m,v))_._k percases ( k = m or k <> m ) ; supposeA3: k = m ; ::_thesis: (W . (a,(p +* (m,b)))) . k = (x +* (m,v)) . k thus (W . (a,(p +* (m,b)))) . k = W . (a,((p +* (m,b)) . k)) by Def9 .= W . (a,b) by A3, Th10 .= (x +* (m,v)) . k by A2, A3, Th13 ; ::_thesis: verum end; supposeA4: k <> m ; ::_thesis: (W . (a,(p +* (m,b)))) . k = (x +* (m,v)) . k thus (W . (a,(p +* (m,b)))) . k = W . (a,((p +* (m,b)) . k)) by Def9 .= W . (a,(p . k)) by A4, FUNCT_7:32 .= x . k by A1, Def9 .= (x +* (m,v)) . k by A4, FUNCT_7:32 ; ::_thesis: verum end; end; end; hence (W . (a,(p +* (m,b)))) . k = (x +* (m,v)) . k ; ::_thesis: verum end; hence W . (a,(p +* (m,b))) = x +* (m,v) by Th14; ::_thesis: verum end; theorem Th26: :: MIDSP_3:26 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let RAS be ReperAlgebra of n; ::_thesis: for a, b being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let a, b be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let W be ATLAS of RAS; ::_thesis: for v being Vector of W for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let v be Vector of W; ::_thesis: for x being Tuple of (n + 1),W st (a,x) . W = p & (a,v) . W = b holds (a,(x +* (m,v))) . W = p +* (m,b) let x be Tuple of (n + 1),W; ::_thesis: ( (a,x) . W = p & (a,v) . W = b implies (a,(x +* (m,v))) . W = p +* (m,b) ) assume ( (a,x) . W = p & (a,v) . W = b ) ; ::_thesis: (a,(x +* (m,v))) . W = p +* (m,b) then ( W . (a,p) = x & W . (a,b) = v ) by Th15, MIDSP_2:33; then W . (a,(p +* (m,b))) = x +* (m,v) by Th25; hence (a,(x +* (m,v))) . W = p +* (m,b) by Th15; ::_thesis: verum end; theorem :: MIDSP_3:27 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS holds ( RAS has_property_of_zero_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS holds ( RAS has_property_of_zero_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for W being ATLAS of RAS holds ( RAS has_property_of_zero_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) let RAS be ReperAlgebra of n; ::_thesis: for W being ATLAS of RAS holds ( RAS has_property_of_zero_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) let W be ATLAS of RAS; ::_thesis: ( RAS has_property_of_zero_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) thus ( RAS has_property_of_zero_in m implies for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) ::_thesis: ( ( for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) implies RAS has_property_of_zero_in m ) proof set a = the Point of RAS; assume A1: RAS has_property_of_zero_in m ; ::_thesis: for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W set b = ( the Point of RAS,(0. W)) . W; let x be Tuple of (n + 1),W; ::_thesis: Phi (x +* (m,(0. W))) = 0. W set p9 = (( the Point of RAS,x) . W) +* (m, the Point of RAS); A2: ( the Point of RAS,(0. W)) . W = the Point of RAS by MIDSP_2:34; then A3: ( the Point of RAS,(x +* (m,(0. W)))) . W = (( the Point of RAS,x) . W) +* (m, the Point of RAS) by Th26; *' ( the Point of RAS,((( the Point of RAS,x) . W) +* (m, the Point of RAS))) = ( the Point of RAS,(0. W)) . W by A1, A2, Def4; hence Phi (x +* (m,(0. W))) = 0. W by A3, Th24; ::_thesis: verum end; thus ( ( for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ) implies RAS has_property_of_zero_in m ) ::_thesis: verum proof assume A4: for x being Tuple of (n + 1),W holds Phi (x +* (m,(0. W))) = 0. W ; ::_thesis: RAS has_property_of_zero_in m for a being Point of RAS for p being Tuple of (n + 1),RAS holds *' (a,(p +* (m,a))) = a proof let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS holds *' (a,(p +* (m,a))) = a let p be Tuple of (n + 1),RAS; ::_thesis: *' (a,(p +* (m,a))) = a set v = W . (a,a); set x9 = (W . (a,p)) +* (m,(0. W)); W . (a,a) = 0. W by MIDSP_2:33; then ( W . (a,(p +* (m,a))) = (W . (a,p)) +* (m,(0. W)) & Phi ((W . (a,p)) +* (m,(0. W))) = W . (a,a) ) by A4, Th25; hence *' (a,(p +* (m,a))) = a by Th23; ::_thesis: verum end; hence RAS has_property_of_zero_in m by Def4; ::_thesis: verum end; end; theorem Th28: :: MIDSP_3:28 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS holds ( RAS is_semi_additive_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS holds ( RAS is_semi_additive_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for W being ATLAS of RAS holds ( RAS is_semi_additive_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) let RAS be ReperAlgebra of n; ::_thesis: for W being ATLAS of RAS holds ( RAS is_semi_additive_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) let W be ATLAS of RAS; ::_thesis: ( RAS is_semi_additive_in m iff for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) thus ( RAS is_semi_additive_in m implies for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) ::_thesis: ( ( for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) implies RAS is_semi_additive_in m ) proof set a = the Point of RAS; assume A1: RAS is_semi_additive_in m ; ::_thesis: for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) let x be Tuple of (n + 1),W; ::_thesis: Phi (x +* (m,(Double (x . m)))) = Double (Phi x) set x9 = x +* (m,(Double (x . m))); set p = ( the Point of RAS,x) . W; set p9 = ( the Point of RAS,(x +* (m,(Double (x . m))))) . W; set q = (( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m))); for i being Nat of n holds (( the Point of RAS,x) . W) . i = ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i proof let i be Nat of n; ::_thesis: (( the Point of RAS,x) . W) . i = ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i now__::_thesis:_((_the_Point_of_RAS,x)_._W)_._i_=_(((_the_Point_of_RAS,(x_+*_(m,(Double_(x_._m)))))_._W)_+*_(m,(_the_Point_of_RAS_@_(((_the_Point_of_RAS,(x_+*_(m,(Double_(x_._m)))))_._W)_._m))))_._i percases ( i = m or i <> m ) ; supposeA2: i = m ; ::_thesis: (( the Point of RAS,x) . W) . i = ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i W . ( the Point of RAS,(( the Point of RAS,x) . W)) = x by Th15; then A3: W . ( the Point of RAS,((( the Point of RAS,x) . W) . m)) = x . m by Def9; W . ( the Point of RAS,(( the Point of RAS,(x +* (m,(Double (x . m))))) . W)) = x +* (m,(Double (x . m))) by Th15; then A4: W . ( the Point of RAS,((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)) = (x +* (m,(Double (x . m)))) . m by Def9; (x +* (m,(Double (x . m)))) . m = Double (x . m) by Th13; then (( the Point of RAS,x) . W) . m = the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m) by A3, A4, MIDSP_2:31 .= ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . m by Th10 ; hence (( the Point of RAS,x) . W) . i = ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i by A2; ::_thesis: verum end; supposeA5: i <> m ; ::_thesis: (( the Point of RAS,x) . W) . i = ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i thus (( the Point of RAS,x) . W) . i = ( the Point of RAS,(x . i)) . W by Def8 .= ( the Point of RAS,((x +* (m,(Double (x . m)))) . i)) . W by A5, FUNCT_7:32 .= (( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . i by Def8 .= ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i by A5, FUNCT_7:32 ; ::_thesis: verum end; end; end; hence (( the Point of RAS,x) . W) . i = ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m)))) . i ; ::_thesis: verum end; then ( the Point of RAS,x) . W = (( the Point of RAS,(x +* (m,(Double (x . m))))) . W) +* (m,( the Point of RAS @ ((( the Point of RAS,(x +* (m,(Double (x . m))))) . W) . m))) by Th9; then *' ( the Point of RAS,(( the Point of RAS,x) . W)) = the Point of RAS @ (*' ( the Point of RAS,(( the Point of RAS,(x +* (m,(Double (x . m))))) . W))) by A1, Def5; then A6: W . ( the Point of RAS,(*' ( the Point of RAS,(( the Point of RAS,(x +* (m,(Double (x . m))))) . W)))) = Double (W . ( the Point of RAS,(*' ( the Point of RAS,(( the Point of RAS,x) . W))))) by MIDSP_2:31; Phi (x +* (m,(Double (x . m)))) = W . ( the Point of RAS,(*' ( the Point of RAS,(( the Point of RAS,(x +* (m,(Double (x . m))))) . W)))) by Lm5; hence Phi (x +* (m,(Double (x . m)))) = Double (Phi x) by A6, Lm5; ::_thesis: verum end; thus ( ( for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ) implies RAS is_semi_additive_in m ) ::_thesis: verum proof assume A7: for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) ; ::_thesis: RAS is_semi_additive_in m let a be Point of RAS; :: according to MIDSP_3:def_5 ::_thesis: for pii being Point of RAS for p being Tuple of (n + 1),RAS st p . m = pii holds *' (a,(p +* (m,(a @ pii)))) = a @ (*' (a,p)) let p9m be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS st p . m = p9m holds *' (a,(p +* (m,(a @ p9m)))) = a @ (*' (a,p)) let p9 be Tuple of (n + 1),RAS; ::_thesis: ( p9 . m = p9m implies *' (a,(p9 +* (m,(a @ p9m)))) = a @ (*' (a,p9)) ) assume A8: p9 . m = p9m ; ::_thesis: *' (a,(p9 +* (m,(a @ p9m)))) = a @ (*' (a,p9)) set p = p9 +* (m,(a @ (p9 . m))); set x = W . (a,(p9 +* (m,(a @ (p9 . m))))); set x9 = (W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m))); W . (a,p9) = (W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m))) proof set y = W . (a,p9); for i being Nat of n holds ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,p9)) . i proof let i be Nat of n; ::_thesis: ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,p9)) . i now__::_thesis:_((W_._(a,(p9_+*_(m,(a_@_(p9_._m))))))_+*_(m,(Double_((W_._(a,(p9_+*_(m,(a_@_(p9_._m))))))_._m))))_._i_=_(W_._(a,p9))_._i percases ( i = m or i <> m ) ; supposeA9: i = m ; ::_thesis: ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,p9)) . i A10: ( W . (a,((p9 +* (m,(a @ (p9 . m)))) . m)) = (W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m & (p9 +* (m,(a @ (p9 . m)))) . m = a @ (p9 . m) ) by Def9, Th10; ( ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . m = Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m) & W . (a,(p9 . m)) = (W . (a,p9)) . m ) by Def9, Th13; hence ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,p9)) . i by A9, A10, MIDSP_2:31; ::_thesis: verum end; supposeA11: i <> m ; ::_thesis: ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,p9)) . i hence ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,(p9 +* (m,(a @ (p9 . m)))))) . i by FUNCT_7:32 .= W . (a,((p9 +* (m,(a @ (p9 . m)))) . i)) by Def9 .= W . (a,(p9 . i)) by A11, FUNCT_7:32 .= (W . (a,p9)) . i by Def9 ; ::_thesis: verum end; end; end; hence ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) . i = (W . (a,p9)) . i ; ::_thesis: verum end; hence W . (a,p9) = (W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m))) by Th14; ::_thesis: verum end; then A12: Phi ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) +* (m,(Double ((W . (a,(p9 +* (m,(a @ (p9 . m)))))) . m)))) = W . (a,(*' (a,p9))) by Lm4; Phi (W . (a,(p9 +* (m,(a @ (p9 . m)))))) = W . (a,(*' (a,(p9 +* (m,(a @ (p9 . m))))))) by Lm4; then W . (a,(*' (a,p9))) = Double (W . (a,(*' (a,(p9 +* (m,(a @ (p9 . m)))))))) by A7, A12; hence *' (a,(p9 +* (m,(a @ p9m)))) = a @ (*' (a,p9)) by A8, MIDSP_2:31; ::_thesis: verum end; end; theorem Th29: :: MIDSP_3:29 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n st RAS has_property_of_zero_in m & RAS is_additive_in m holds RAS is_semi_additive_in m proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n st RAS has_property_of_zero_in m & RAS is_additive_in m holds RAS is_semi_additive_in m let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n st RAS has_property_of_zero_in m & RAS is_additive_in m holds RAS is_semi_additive_in m let RAS be ReperAlgebra of n; ::_thesis: ( RAS has_property_of_zero_in m & RAS is_additive_in m implies RAS is_semi_additive_in m ) assume that A1: RAS has_property_of_zero_in m and A2: RAS is_additive_in m ; ::_thesis: RAS is_semi_additive_in m let a be Point of RAS; :: according to MIDSP_3:def_5 ::_thesis: for pii being Point of RAS for p being Tuple of (n + 1),RAS st p . m = pii holds *' (a,(p +* (m,(a @ pii)))) = a @ (*' (a,p)) let pm be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS st p . m = pm holds *' (a,(p +* (m,(a @ pm)))) = a @ (*' (a,p)) let p be Tuple of (n + 1),RAS; ::_thesis: ( p . m = pm implies *' (a,(p +* (m,(a @ pm)))) = a @ (*' (a,p)) ) assume p . m = pm ; ::_thesis: *' (a,(p +* (m,(a @ pm)))) = a @ (*' (a,p)) then *' (a,(p +* (m,(a @ pm)))) = (*' (a,p)) @ (*' (a,(p +* (m,a)))) by A2, Def6 .= a @ (*' (a,p)) by A1, Def4 ; hence *' (a,(p +* (m,(a @ pm)))) = a @ (*' (a,p)) ; ::_thesis: verum end; Lm6: for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st RAS is_semi_additive_in m holds for a, p9m, p99m being Point of RAS for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st RAS is_semi_additive_in m holds for a, p9m, p99m being Point of RAS for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for W being ATLAS of RAS st RAS is_semi_additive_in m holds for a, p9m, p99m being Point of RAS for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) let RAS be ReperAlgebra of n; ::_thesis: for W being ATLAS of RAS st RAS is_semi_additive_in m holds for a, p9m, p99m being Point of RAS for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) let W be ATLAS of RAS; ::_thesis: ( RAS is_semi_additive_in m implies for a, p9m, p99m being Point of RAS for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) ) assume A1: RAS is_semi_additive_in m ; ::_thesis: for a, p9m, p99m being Point of RAS for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) let a, p9m, p99m be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS st a @ p99m = (p . m) @ p9m holds ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) let p be Tuple of (n + 1),RAS; ::_thesis: ( a @ p99m = (p . m) @ p9m implies ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) ) assume a @ p99m = (p . m) @ p9m ; ::_thesis: ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) then *' (a,(p +* (m,((p . m) @ p9m)))) = a @ (*' (a,(p +* (m,p99m)))) by A1, Th11; hence ( *' (a,(p +* (m,((p . m) @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) iff W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) ) by MIDSP_2:30; ::_thesis: verum end; Lm7: for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) holds RAS is_semi_additive_in m proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) holds RAS is_semi_additive_in m let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for W being ATLAS of RAS st ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) holds RAS is_semi_additive_in m let RAS be ReperAlgebra of n; ::_thesis: for W being ATLAS of RAS st ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) holds RAS is_semi_additive_in m let W be ATLAS of RAS; ::_thesis: ( ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) implies RAS is_semi_additive_in m ) assume A1: for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ; ::_thesis: RAS is_semi_additive_in m for x being Tuple of (n + 1),W holds Phi (x +* (m,(Double (x . m)))) = Double (Phi x) proof let x be Tuple of (n + 1),W; ::_thesis: Phi (x +* (m,(Double (x . m)))) = Double (Phi x) set v = x . m; set y = x +* (m,(x . m)); for k being Nat of n holds (x +* (m,(x . m))) . k = x . k proof let k be Nat of n; ::_thesis: (x +* (m,(x . m))) . k = x . k now__::_thesis:_(x_+*_(m,(x_._m)))_._k_=_x_._k percases ( k = m or k <> m ) ; suppose k = m ; ::_thesis: (x +* (m,(x . m))) . k = x . k hence (x +* (m,(x . m))) . k = x . k by Th13; ::_thesis: verum end; suppose k <> m ; ::_thesis: (x +* (m,(x . m))) . k = x . k hence (x +* (m,(x . m))) . k = x . k by FUNCT_7:32; ::_thesis: verum end; end; end; hence (x +* (m,(x . m))) . k = x . k ; ::_thesis: verum end; then A2: x +* (m,(x . m)) = x by Th14; thus Phi (x +* (m,(Double (x . m)))) = Phi (x +* (m,((x . m) + (x . m)))) by MIDSP_2:def_1 .= (Phi x) + (Phi (x +* (m,(x . m)))) by A1 .= Double (Phi x) by A2, MIDSP_2:def_1 ; ::_thesis: verum end; hence RAS is_semi_additive_in m by Th28; ::_thesis: verum end; theorem :: MIDSP_3:30 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st RAS has_property_of_zero_in m holds ( RAS is_additive_in m iff for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st RAS has_property_of_zero_in m holds ( RAS is_additive_in m iff for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for W being ATLAS of RAS st RAS has_property_of_zero_in m holds ( RAS is_additive_in m iff for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) let RAS be ReperAlgebra of n; ::_thesis: for W being ATLAS of RAS st RAS has_property_of_zero_in m holds ( RAS is_additive_in m iff for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) let W be ATLAS of RAS; ::_thesis: ( RAS has_property_of_zero_in m implies ( RAS is_additive_in m iff for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) ) assume A1: RAS has_property_of_zero_in m ; ::_thesis: ( RAS is_additive_in m iff for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) thus ( RAS is_additive_in m implies for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) ::_thesis: ( ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) implies RAS is_additive_in m ) proof set a = the Point of RAS; assume A2: RAS is_additive_in m ; ::_thesis: for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) let x be Tuple of (n + 1),W; ::_thesis: for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) let v be Vector of W; ::_thesis: Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) set p = ( the Point of RAS,x) . W; set p9m = ( the Point of RAS,v) . W; consider p99m being Point of RAS such that A3: p99m @ the Point of RAS = ((( the Point of RAS,x) . W) . m) @ (( the Point of RAS,v) . W) by MIDSP_1:def_3; A4: ( W . ( the Point of RAS,(( the Point of RAS,x) . W)) = x & W . ( the Point of RAS,(( the Point of RAS,v) . W)) = v ) by Th15, MIDSP_2:33; A5: W . ( the Point of RAS,p99m) = (W . ( the Point of RAS,((( the Point of RAS,x) . W) . m))) + (W . ( the Point of RAS,(( the Point of RAS,v) . W))) by A3, MIDSP_2:30 .= (x . m) + v by A4, Def9 ; (( the Point of RAS,x) . W) +* (m,p99m) = ( the Point of RAS,(x +* (m,((x . m) + v)))) . W proof set pp = (( the Point of RAS,x) . W) +* (m,p99m); set xx = x +* (m,((x . m) + v)); set qq = ( the Point of RAS,(x +* (m,((x . m) + v)))) . W; for i being Nat of n holds ((( the Point of RAS,x) . W) +* (m,p99m)) . i = (( the Point of RAS,(x +* (m,((x . m) + v)))) . W) . i proof let i be Nat of n; ::_thesis: ((( the Point of RAS,x) . W) +* (m,p99m)) . i = (( the Point of RAS,(x +* (m,((x . m) + v)))) . W) . i percases ( i = m or i <> m ) ; supposeA6: i = m ; ::_thesis: ((( the Point of RAS,x) . W) +* (m,p99m)) . i = (( the Point of RAS,(x +* (m,((x . m) + v)))) . W) . i hence ((( the Point of RAS,x) . W) +* (m,p99m)) . i = p99m by Th10 .= ( the Point of RAS,((x . m) + v)) . W by A5, MIDSP_2:33 .= ( the Point of RAS,((x +* (m,((x . m) + v))) . m)) . W by Th13 .= (( the Point of RAS,(x +* (m,((x . m) + v)))) . W) . i by A6, Def8 ; ::_thesis: verum end; supposeA7: i <> m ; ::_thesis: ((( the Point of RAS,x) . W) +* (m,p99m)) . i = (( the Point of RAS,(x +* (m,((x . m) + v)))) . W) . i hence ((( the Point of RAS,x) . W) +* (m,p99m)) . i = (( the Point of RAS,x) . W) . i by FUNCT_7:32 .= ( the Point of RAS,(x . i)) . W by Def8 .= ( the Point of RAS,((x +* (m,((x . m) + v))) . i)) . W by A7, FUNCT_7:32 .= (( the Point of RAS,(x +* (m,((x . m) + v)))) . W) . i by Def8 ; ::_thesis: verum end; end; end; hence (( the Point of RAS,x) . W) +* (m,p99m) = ( the Point of RAS,(x +* (m,((x . m) + v)))) . W by Th9; ::_thesis: verum end; then A8: Phi (x +* (m,((x . m) + v))) = W . ( the Point of RAS,(*' ( the Point of RAS,((( the Point of RAS,x) . W) +* (m,p99m))))) by Lm5; A9: (( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W)) = ( the Point of RAS,(x +* (m,v))) . W proof set pp = (( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W)); set qq = ( the Point of RAS,(x +* (m,v))) . W; for i being Nat of n holds ((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))) . i = (( the Point of RAS,(x +* (m,v))) . W) . i proof let i be Nat of n; ::_thesis: ((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))) . i = (( the Point of RAS,(x +* (m,v))) . W) . i percases ( i = m or i <> m ) ; supposeA10: i = m ; ::_thesis: ((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))) . i = (( the Point of RAS,(x +* (m,v))) . W) . i hence ((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))) . i = ( the Point of RAS,v) . W by Th10 .= ( the Point of RAS,((x +* (m,v)) . m)) . W by Th13 .= (( the Point of RAS,(x +* (m,v))) . W) . i by A10, Def8 ; ::_thesis: verum end; supposeA11: i <> m ; ::_thesis: ((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))) . i = (( the Point of RAS,(x +* (m,v))) . W) . i hence ((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))) . i = (( the Point of RAS,x) . W) . i by FUNCT_7:32 .= ( the Point of RAS,(x . i)) . W by Def8 .= ( the Point of RAS,((x +* (m,v)) . i)) . W by A11, FUNCT_7:32 .= (( the Point of RAS,(x +* (m,v))) . W) . i by Def8 ; ::_thesis: verum end; end; end; hence (( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W)) = ( the Point of RAS,(x +* (m,v))) . W by Th9; ::_thesis: verum end; ( RAS is_semi_additive_in m & *' ( the Point of RAS,((( the Point of RAS,x) . W) +* (m,(((( the Point of RAS,x) . W) . m) @ (( the Point of RAS,v) . W))))) = (*' ( the Point of RAS,(( the Point of RAS,x) . W))) @ (*' ( the Point of RAS,((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))))) ) by A1, A2, Def6, Th29; then A12: W . ( the Point of RAS,(*' ( the Point of RAS,((( the Point of RAS,x) . W) +* (m,p99m))))) = (W . ( the Point of RAS,(*' ( the Point of RAS,(( the Point of RAS,x) . W))))) + (W . ( the Point of RAS,(*' ( the Point of RAS,((( the Point of RAS,x) . W) +* (m,(( the Point of RAS,v) . W))))))) by A3, Lm6; Phi x = W . ( the Point of RAS,(*' ( the Point of RAS,(( the Point of RAS,x) . W)))) by Lm5; hence Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) by A12, A8, A9, Lm5; ::_thesis: verum end; thus ( ( for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ) implies RAS is_additive_in m ) ::_thesis: verum proof assume A13: for x being Tuple of (n + 1),W for v being Vector of W holds Phi (x +* (m,((x . m) + v))) = (Phi x) + (Phi (x +* (m,v))) ; ::_thesis: RAS is_additive_in m then A14: RAS is_semi_additive_in m by Lm7; for a, pm, p9m being Point of RAS for p being Tuple of (n + 1),RAS st p . m = pm holds *' (a,(p +* (m,(pm @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) proof let a, pm, p9m be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS st p . m = pm holds *' (a,(p +* (m,(pm @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) let p be Tuple of (n + 1),RAS; ::_thesis: ( p . m = pm implies *' (a,(p +* (m,(pm @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) ) assume A15: p . m = pm ; ::_thesis: *' (a,(p +* (m,(pm @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) set x = W . (a,p); set v = W . (a,p9m); consider p99m being Point of RAS such that A16: p99m @ a = (p . m) @ p9m by MIDSP_1:def_3; A17: (a,(W . (a,p))) . W = p by Th15; A18: W . (a,p99m) = (W . (a,(p . m))) + (W . (a,p9m)) by A16, MIDSP_2:30 .= ((W . (a,p)) . m) + (W . (a,p9m)) by Def9 ; p +* (m,p99m) = (a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W proof set pp = p +* (m,p99m); set xx = (W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))); set qq = (a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W; for i being Nat of n holds (p +* (m,p99m)) . i = ((a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W) . i proof let i be Nat of n; ::_thesis: (p +* (m,p99m)) . i = ((a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W) . i percases ( i = m or i <> m ) ; supposeA19: i = m ; ::_thesis: (p +* (m,p99m)) . i = ((a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W) . i hence (p +* (m,p99m)) . i = p99m by Th10 .= (a,(((W . (a,p)) . m) + (W . (a,p9m)))) . W by A18, MIDSP_2:33 .= (a,(((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m))))) . m)) . W by Th13 .= ((a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W) . i by A19, Def8 ; ::_thesis: verum end; supposeA20: i <> m ; ::_thesis: (p +* (m,p99m)) . i = ((a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W) . i hence (p +* (m,p99m)) . i = p . i by FUNCT_7:32 .= (a,((W . (a,p)) . i)) . W by A17, Def8 .= (a,(((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m))))) . i)) . W by A20, FUNCT_7:32 .= ((a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W) . i by Def8 ; ::_thesis: verum end; end; end; hence p +* (m,p99m) = (a,((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m)))))) . W by Th9; ::_thesis: verum end; then A21: Phi ((W . (a,p)) +* (m,(((W . (a,p)) . m) + (W . (a,p9m))))) = W . (a,(*' (a,(p +* (m,p99m))))) by Lm5; A22: (a,(W . (a,p9m))) . W = p9m by MIDSP_2:33; p +* (m,p9m) = (a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W proof set pp = p +* (m,p9m); set qq = (a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W; for i being Nat of n holds (p +* (m,p9m)) . i = ((a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W) . i proof let i be Nat of n; ::_thesis: (p +* (m,p9m)) . i = ((a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W) . i percases ( i = m or i <> m ) ; supposeA23: i = m ; ::_thesis: (p +* (m,p9m)) . i = ((a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W) . i hence (p +* (m,p9m)) . i = p9m by Th10 .= (a,(((W . (a,p)) +* (m,(W . (a,p9m)))) . m)) . W by A22, Th13 .= ((a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W) . i by A23, Def8 ; ::_thesis: verum end; supposeA24: i <> m ; ::_thesis: (p +* (m,p9m)) . i = ((a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W) . i hence (p +* (m,p9m)) . i = p . i by FUNCT_7:32 .= (a,((W . (a,p)) . i)) . W by A17, Def8 .= (a,(((W . (a,p)) +* (m,(W . (a,p9m)))) . i)) . W by A24, FUNCT_7:32 .= ((a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W) . i by Def8 ; ::_thesis: verum end; end; end; hence p +* (m,p9m) = (a,((W . (a,p)) +* (m,(W . (a,p9m))))) . W by Th9; ::_thesis: verum end; then A25: Phi ((W . (a,p)) +* (m,(W . (a,p9m)))) = W . (a,(*' (a,(p +* (m,p9m))))) by Lm5; Phi (W . (a,p)) = W . (a,(*' (a,p))) by Lm4; then W . (a,(*' (a,(p +* (m,p99m))))) = (W . (a,(*' (a,p)))) + (W . (a,(*' (a,(p +* (m,p9m)))))) by A13, A21, A25; hence *' (a,(p +* (m,(pm @ p9m)))) = (*' (a,p)) @ (*' (a,(p +* (m,p9m)))) by A14, A15, A16, Lm6; ::_thesis: verum end; hence RAS is_additive_in m by Def6; ::_thesis: verum end; end; theorem Th31: :: MIDSP_3:31 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) let RAS be ReperAlgebra of n; ::_thesis: for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) let W be ATLAS of RAS; ::_thesis: for x being Tuple of (n + 1),W st W . (a,p) = x & m <= n holds W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) let x be Tuple of (n + 1),W; ::_thesis: ( W . (a,p) = x & m <= n implies W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) ) assume that A1: W . (a,p) = x and A2: m <= n ; ::_thesis: W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) reconsider m9 = m + 1 as Nat of n by A2, Th8; set y = W . (a,(p +* (m9,(p . m)))); set z = x +* (m9,(x . m)); for k being Nat of n holds (W . (a,(p +* (m9,(p . m))))) . k = (x +* (m9,(x . m))) . k proof let k be Nat of n; ::_thesis: (W . (a,(p +* (m9,(p . m))))) . k = (x +* (m9,(x . m))) . k now__::_thesis:_(W_._(a,(p_+*_(m9,(p_._m)))))_._k_=_(x_+*_(m9,(x_._m)))_._k percases ( k = m9 or k <> m9 ) ; supposeA3: k = m9 ; ::_thesis: (W . (a,(p +* (m9,(p . m))))) . k = (x +* (m9,(x . m))) . k thus (W . (a,(p +* (m9,(p . m))))) . k = W . (a,((p +* (m9,(p . m))) . k)) by Def9 .= W . (a,(p . m)) by A3, Th10 .= x . m by A1, Def9 .= (x +* (m9,(x . m))) . k by A3, Th13 ; ::_thesis: verum end; supposeA4: k <> m9 ; ::_thesis: (W . (a,(p +* (m9,(p . m))))) . k = (x +* (m9,(x . m))) . k thus (W . (a,(p +* (m9,(p . m))))) . k = W . (a,((p +* (m9,(p . m))) . k)) by Def9 .= W . (a,(p . k)) by A4, FUNCT_7:32 .= x . k by A1, Def9 .= (x +* (m9,(x . m))) . k by A4, FUNCT_7:32 ; ::_thesis: verum end; end; end; hence (W . (a,(p +* (m9,(p . m))))) . k = (x +* (m9,(x . m))) . k ; ::_thesis: verum end; hence W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) by Th14; ::_thesis: verum end; theorem Th32: :: MIDSP_3:32 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) let RAS be ReperAlgebra of n; ::_thesis: for a being Point of RAS for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) let p be Tuple of (n + 1),RAS; ::_thesis: for W being ATLAS of RAS for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) let W be ATLAS of RAS; ::_thesis: for x being Tuple of (n + 1),W st (a,x) . W = p & m <= n holds (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) let x be Tuple of (n + 1),W; ::_thesis: ( (a,x) . W = p & m <= n implies (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) ) assume that A1: (a,x) . W = p and A2: m <= n ; ::_thesis: (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) W . (a,p) = x by A1, Th15; then W . (a,(p +* ((m + 1),(p . m)))) = x +* ((m + 1),(x . m)) by A2, Th31; hence (a,(x +* ((m + 1),(x . m)))) . W = p +* ((m + 1),(p . m)) by Th15; ::_thesis: verum end; theorem :: MIDSP_3:33 for n being Element of NAT for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st m <= n holds ( RAS is_alternative_in m iff for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) proof let n be Element of NAT ; ::_thesis: for m being Nat of n for RAS being ReperAlgebra of n for W being ATLAS of RAS st m <= n holds ( RAS is_alternative_in m iff for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) let m be Nat of n; ::_thesis: for RAS being ReperAlgebra of n for W being ATLAS of RAS st m <= n holds ( RAS is_alternative_in m iff for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) let RAS be ReperAlgebra of n; ::_thesis: for W being ATLAS of RAS st m <= n holds ( RAS is_alternative_in m iff for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) let W be ATLAS of RAS; ::_thesis: ( m <= n implies ( RAS is_alternative_in m iff for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) ) assume A1: m <= n ; ::_thesis: ( RAS is_alternative_in m iff for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) thus ( RAS is_alternative_in m implies for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) ::_thesis: ( ( for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ) implies RAS is_alternative_in m ) proof set a = the Point of RAS; assume A2: RAS is_alternative_in m ; ::_thesis: for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W let x be Tuple of (n + 1),W; ::_thesis: Phi (x +* ((m + 1),(x . m))) = 0. W set p = ( the Point of RAS,x) . W; set b = ( the Point of RAS,(0. W)) . W; set p9 = (( the Point of RAS,x) . W) +* ((m + 1),((( the Point of RAS,x) . W) . m)); ( the Point of RAS,(0. W)) . W = the Point of RAS by MIDSP_2:34; then A3: *' ( the Point of RAS,((( the Point of RAS,x) . W) +* ((m + 1),((( the Point of RAS,x) . W) . m)))) = ( the Point of RAS,(0. W)) . W by A2, Def7; ( the Point of RAS,(x +* ((m + 1),(x . m)))) . W = (( the Point of RAS,x) . W) +* ((m + 1),((( the Point of RAS,x) . W) . m)) by A1, Th32; hence Phi (x +* ((m + 1),(x . m))) = 0. W by A3, Th24; ::_thesis: verum end; assume A4: for x being Tuple of (n + 1),W holds Phi (x +* ((m + 1),(x . m))) = 0. W ; ::_thesis: RAS is_alternative_in m for a being Point of RAS for p being Tuple of (n + 1),RAS for pm being Point of RAS st p . m = pm holds *' (a,(p +* ((m + 1),pm))) = a proof let a be Point of RAS; ::_thesis: for p being Tuple of (n + 1),RAS for pm being Point of RAS st p . m = pm holds *' (a,(p +* ((m + 1),pm))) = a let p be Tuple of (n + 1),RAS; ::_thesis: for pm being Point of RAS st p . m = pm holds *' (a,(p +* ((m + 1),pm))) = a let pm be Point of RAS; ::_thesis: ( p . m = pm implies *' (a,(p +* ((m + 1),pm))) = a ) assume A5: p . m = pm ; ::_thesis: *' (a,(p +* ((m + 1),pm))) = a set x = W . (a,p); set v = W . (a,a); set x9 = (W . (a,p)) +* ((m + 1),((W . (a,p)) . m)); W . (a,a) = 0. W by MIDSP_2:33; then A6: Phi ((W . (a,p)) +* ((m + 1),((W . (a,p)) . m))) = W . (a,a) by A4; W . (a,(p +* ((m + 1),(p . m)))) = (W . (a,p)) +* ((m + 1),((W . (a,p)) . m)) by A1, Th31; hence *' (a,(p +* ((m + 1),pm))) = a by A5, A6, Th23; ::_thesis: verum end; hence RAS is_alternative_in m by Def7; ::_thesis: verum end;