:: NFCONT_1 semantic presentation

definition
let c1, c2 be 1-sorted ;
mode PartFunc of a1,a2 is PartFunc of the carrier of a1,the carrier of a2;
end;

definition
let c1 be RealLinearSpace;
let c2 be sequence of c1;
func - c2 -> sequence of a1 means :Def1: :: NFCONT_1:def 1
for b1 being Nat holds a3 . b1 = - (a2 . b1);
existence
ex b1 being sequence of c1 st
for b2 being Nat holds b1 . b2 = - (c2 . b2)
proof end;
uniqueness
for b1, b2 being sequence of c1 st ( for b3 being Nat holds b1 . b3 = - (c2 . b3) ) & ( for b3 being Nat holds b2 . b3 = - (c2 . b3) ) holds
b1 = b2
proof end;
end;

:: deftheorem Def1 defines - NFCONT_1:def 1 :
for b1 being RealLinearSpace
for b2, b3 being sequence of b1 holds
( b3 = - b2 iff for b4 being Nat holds b3 . b4 = - (b2 . b4) );

theorem Th1: :: NFCONT_1:1
for b1 being RealNormSpace
for b2, b3 being sequence of b1 holds b2 - b3 = b2 + (- b3)
proof end;

theorem Th2: :: NFCONT_1:2
for b1 being RealNormSpace
for b2 being sequence of b1 holds - b2 = (- 1) * b2
proof end;

definition
let c1, c2 be RealNormSpace;
let c3 be PartFunc of c1,c2;
func ||.c3.|| -> PartFunc of the carrier of a1, REAL means :Def2: :: NFCONT_1:def 2
( dom a4 = dom a3 & ( for b1 being Point of a1 st b1 in dom a4 holds
a4 . b1 = ||.(a3 /. b1).|| ) );
existence
ex b1 being PartFunc of the carrier of c1, REAL st
( dom b1 = dom c3 & ( for b2 being Point of c1 st b2 in dom b1 holds
b1 . b2 = ||.(c3 /. b2).|| ) )
proof end;
uniqueness
for b1, b2 being PartFunc of the carrier of c1, REAL st dom b1 = dom c3 & ( for b3 being Point of c1 st b3 in dom b1 holds
b1 . b3 = ||.(c3 /. b3).|| ) & dom b2 = dom c3 & ( for b3 being Point of c1 st b3 in dom b2 holds
b2 . b3 = ||.(c3 /. b3).|| ) holds
b1 = b2
proof end;
end;

:: deftheorem Def2 defines ||. NFCONT_1:def 2 :
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being PartFunc of the carrier of b1, REAL holds
( b4 = ||.b3.|| iff ( dom b4 = dom b3 & ( for b5 being Point of b1 st b5 in dom b4 holds
b4 . b5 = ||.(b3 /. b5).|| ) ) );

definition
let c1 be RealNormSpace;
let c2 be Point of c1;
mode Neighbourhood of c2 -> Subset of a1 means :Def3: :: NFCONT_1:def 3
ex b1 being Real st
( 0 < b1 & { b2 where B is Point of a1 : ||.(b2 - a2).|| < b1 } c= a3 );
existence
ex b1 being Subset of c1ex b2 being Real st
( 0 < b2 & { b3 where B is Point of c1 : ||.(b3 - c2).|| < b2 } c= b1 )
proof end;
end;

:: deftheorem Def3 defines Neighbourhood NFCONT_1:def 3 :
for b1 being RealNormSpace
for b2 being Point of b1
for b3 being Subset of b1 holds
( b3 is Neighbourhood of b2 iff ex b4 being Real st
( 0 < b4 & { b5 where B is Point of b1 : ||.(b5 - b2).|| < b4 } c= b3 ) );

theorem Th3: :: NFCONT_1:3
for b1 being RealNormSpace
for b2 being Point of b1
for b3 being Real st 0 < b3 holds
{ b4 where B is Point of b1 : ||.(b4 - b2).|| < b3 } is Neighbourhood of b2
proof end;

theorem Th4: :: NFCONT_1:4
for b1 being RealNormSpace
for b2 being Point of b1
for b3 being Neighbourhood of b2 holds b2 in b3
proof end;

definition
let c1 be RealNormSpace;
let c2 be Subset of c1;
attr a2 is compact means :Def4: :: NFCONT_1:def 4
for b1 being sequence of a1 st rng b1 c= a2 holds
ex b2 being sequence of a1 st
( b2 is subsequence of b1 & b2 is convergent & lim b2 in a2 );
end;

:: deftheorem Def4 defines compact NFCONT_1:def 4 :
for b1 being RealNormSpace
for b2 being Subset of b1 holds
( b2 is compact iff for b3 being sequence of b1 st rng b3 c= b2 holds
ex b4 being sequence of b1 st
( b4 is subsequence of b3 & b4 is convergent & lim b4 in b2 ) );

definition
let c1 be RealNormSpace;
let c2 be Subset of c1;
attr a2 is closed means :: NFCONT_1:def 5
for b1 being sequence of a1 st rng b1 c= a2 & b1 is convergent holds
lim b1 in a2;
end;

:: deftheorem Def5 defines closed NFCONT_1:def 5 :
for b1 being RealNormSpace
for b2 being Subset of b1 holds
( b2 is closed iff for b3 being sequence of b1 st rng b3 c= b2 & b3 is convergent holds
lim b3 in b2 );

definition
let c1 be RealNormSpace;
let c2 be Subset of c1;
attr a2 is open means :: NFCONT_1:def 6
a2 ` is closed;
end;

:: deftheorem Def6 defines open NFCONT_1:def 6 :
for b1 being RealNormSpace
for b2 being Subset of b1 holds
( b2 is open iff b2 ` is closed );

definition
let c1, c2 be RealNormSpace;
let c3 be PartFunc of c1,c2;
let c4 be sequence of c1;
assume E8: rng c4 c= dom c3 ;
func c3 * c4 -> sequence of a2 equals :Def7: :: NFCONT_1:def 7
a3 * a4;
coherence
c3 * c4 is sequence of c2
proof end;
end;

:: deftheorem Def7 defines * NFCONT_1:def 7 :
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being sequence of b1 st rng b4 c= dom b3 holds
b3 * b4 = b3 * b4;

definition
let c1 be RealNormSpace;
let c2 be PartFunc of the carrier of c1, REAL ;
let c3 be sequence of c1;
assume E9: rng c3 c= dom c2 ;
func c2 * c3 -> Real_Sequence equals :Def8: :: NFCONT_1:def 8
a2 * a3;
coherence
c2 * c3 is Real_Sequence
proof end;
end;

:: deftheorem Def8 defines * NFCONT_1:def 8 :
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3 being sequence of b1 st rng b3 c= dom b2 holds
b2 * b3 = b2 * b3;

definition
let c1, c2 be RealNormSpace;
let c3 be PartFunc of c1,c2;
let c4 be Point of c1;
pred c3 is_continuous_in c4 means :Def9: :: NFCONT_1:def 9
( a4 in dom a3 & ( for b1 being sequence of a1 st rng b1 c= dom a3 & b1 is convergent & lim b1 = a4 holds
( a3 * b1 is convergent & a3 /. a4 = lim (a3 * b1) ) ) );
end;

:: deftheorem Def9 defines is_continuous_in NFCONT_1:def 9 :
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being Point of b1 holds
( b3 is_continuous_in b4 iff ( b4 in dom b3 & ( for b5 being sequence of b1 st rng b5 c= dom b3 & b5 is convergent & lim b5 = b4 holds
( b3 * b5 is convergent & b3 /. b4 = lim (b3 * b5) ) ) ) );

definition
let c1 be RealNormSpace;
let c2 be PartFunc of the carrier of c1, REAL ;
let c3 be Point of c1;
pred c2 is_continuous_in c3 means :Def10: :: NFCONT_1:def 10
( a3 in dom a2 & ( for b1 being sequence of a1 st rng b1 c= dom a2 & b1 is convergent & lim b1 = a3 holds
( a2 * b1 is convergent & a2 /. a3 = lim (a2 * b1) ) ) );
end;

:: deftheorem Def10 defines is_continuous_in NFCONT_1:def 10 :
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3 being Point of b1 holds
( b2 is_continuous_in b3 iff ( b3 in dom b2 & ( for b4 being sequence of b1 st rng b4 c= dom b2 & b4 is convergent & lim b4 = b3 holds
( b2 * b4 is convergent & b2 /. b3 = lim (b2 * b4) ) ) ) );

theorem Th5: :: NFCONT_1:5
for b1 being Nat
for b2, b3 being RealNormSpace
for b4 being sequence of b2
for b5 being PartFunc of b2,b3 st rng b4 c= dom b5 holds
b4 . b1 in dom b5
proof end;

theorem Th6: :: NFCONT_1:6
for b1 being RealNormSpace
for b2 being sequence of b1
for b3 being set holds
( b3 in rng b2 iff ex b4 being Nat st b3 = b2 . b4 )
proof end;

theorem Th7: :: NFCONT_1:7
for b1 being RealNormSpace
for b2, b3 being sequence of b1 st b3 is subsequence of b2 holds
rng b3 c= rng b2
proof end;

theorem Th8: :: NFCONT_1:8
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being sequence of b2 st rng b4 c= dom b3 holds
for b5 being Nat holds (b3 * b4) . b5 = b3 /. (b4 . b5)
proof end;

theorem Th9: :: NFCONT_1:9
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3 being sequence of b1 st rng b3 c= dom b2 holds
for b4 being Nat holds (b2 * b3) . b4 = b2 /. (b3 . b4)
proof end;

theorem Th10: :: NFCONT_1:10
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being sequence of b1
for b5 being increasing Seq_of_Nat st rng b4 c= dom b3 holds
(b3 * b4) * b5 = b3 * (b4 * b5)
proof end;

theorem Th11: :: NFCONT_1:11
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3 being sequence of b1
for b4 being increasing Seq_of_Nat st rng b3 c= dom b2 holds
(b2 * b3) * b4 = b2 * (b3 * b4)
proof end;

theorem Th12: :: NFCONT_1:12
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4, b5 being sequence of b1 st rng b4 c= dom b3 & b5 is subsequence of b4 holds
b3 * b5 is subsequence of b3 * b4
proof end;

theorem Th13: :: NFCONT_1:13
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3, b4 being sequence of b1 st rng b3 c= dom b2 & b4 is subsequence of b3 holds
b2 * b4 is subsequence of b2 * b3
proof end;

theorem Th14: :: NFCONT_1:14
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Point of b2 holds
( b3 is_continuous_in b4 iff ( b4 in dom b3 & ( for b5 being Real st 0 < b5 holds
ex b6 being Real st
( 0 < b6 & ( for b7 being Point of b2 st b7 in dom b3 & ||.(b7 - b4).|| < b6 holds
||.((b3 /. b7) - (b3 /. b4)).|| < b5 ) ) ) ) )
proof end;

theorem Th15: :: NFCONT_1:15
for b1 being RealNormSpace
for b2 being Point of b1
for b3 being PartFunc of the carrier of b1, REAL holds
( b3 is_continuous_in b2 iff ( b2 in dom b3 & ( for b4 being Real st 0 < b4 holds
ex b5 being Real st
( 0 < b5 & ( for b6 being Point of b1 st b6 in dom b3 & ||.(b6 - b2).|| < b5 holds
abs ((b3 /. b6) - (b3 /. b2)) < b4 ) ) ) ) )
proof end;

theorem Th16: :: NFCONT_1:16
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Point of b2 holds
( b3 is_continuous_in b4 iff ( b4 in dom b3 & ( for b5 being Neighbourhood of b3 /. b4 ex b6 being Neighbourhood of b4 st
for b7 being Point of b2 st b7 in dom b3 & b7 in b6 holds
b3 /. b7 in b5 ) ) )
proof end;

theorem Th17: :: NFCONT_1:17
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Point of b2 holds
( b3 is_continuous_in b4 iff ( b4 in dom b3 & ( for b5 being Neighbourhood of b3 /. b4 ex b6 being Neighbourhood of b4 st b3 .: b6 c= b5 ) ) )
proof end;

theorem Th18: :: NFCONT_1:18
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Point of b2 st b4 in dom b3 & ex b5 being Neighbourhood of b4 st (dom b3) /\ b5 = {b4} holds
b3 is_continuous_in b4
proof end;

theorem Th19: :: NFCONT_1:19
for b1, b2 being RealNormSpace
for b3, b4 being PartFunc of b1,b2
for b5 being sequence of b1 st rng b5 c= (dom b3) /\ (dom b4) holds
( (b3 + b4) * b5 = (b3 * b5) + (b4 * b5) & (b3 - b4) * b5 = (b3 * b5) - (b4 * b5) )
proof end;

theorem Th20: :: NFCONT_1:20
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being sequence of b1
for b5 being Real st rng b4 c= dom b3 holds
(b5 (#) b3) * b4 = b5 * (b3 * b4)
proof end;

theorem Th21: :: NFCONT_1:21
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being sequence of b1 st rng b4 c= dom b3 holds
( ||.(b3 * b4).|| = ||.b3.|| * b4 & - (b3 * b4) = (- b3) * b4 )
proof end;

theorem Th22: :: NFCONT_1:22
for b1, b2 being RealNormSpace
for b3, b4 being PartFunc of b2,b1
for b5 being Point of b2 st b3 is_continuous_in b5 & b4 is_continuous_in b5 holds
( b3 + b4 is_continuous_in b5 & b3 - b4 is_continuous_in b5 )
proof end;

theorem Th23: :: NFCONT_1:23
for b1 being Real
for b2, b3 being RealNormSpace
for b4 being PartFunc of b3,b2
for b5 being Point of b3 st b4 is_continuous_in b5 holds
b1 (#) b4 is_continuous_in b5
proof end;

theorem Th24: :: NFCONT_1:24
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Point of b2 st b3 is_continuous_in b4 holds
( ||.b3.|| is_continuous_in b4 & - b3 is_continuous_in b4 )
proof end;

definition
let c1, c2 be RealNormSpace;
let c3 be PartFunc of c1,c2;
let c4 be set ;
pred c3 is_continuous_on c4 means :Def11: :: NFCONT_1:def 11
( a4 c= dom a3 & ( for b1 being Point of a1 st b1 in a4 holds
a3 | a4 is_continuous_in b1 ) );
end;

:: deftheorem Def11 defines is_continuous_on NFCONT_1:def 11 :
for b1, b2 being RealNormSpace
for b3 being PartFunc of b1,b2
for b4 being set holds
( b3 is_continuous_on b4 iff ( b4 c= dom b3 & ( for b5 being Point of b1 st b5 in b4 holds
b3 | b4 is_continuous_in b5 ) ) );

definition
let c1 be RealNormSpace;
let c2 be PartFunc of the carrier of c1, REAL ;
let c3 be set ;
pred c2 is_continuous_on c3 means :Def12: :: NFCONT_1:def 12
( a3 c= dom a2 & ( for b1 being Point of a1 st b1 in a3 holds
a2 | a3 is_continuous_in b1 ) );
end;

:: deftheorem Def12 defines is_continuous_on NFCONT_1:def 12 :
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3 being set holds
( b2 is_continuous_on b3 iff ( b3 c= dom b2 & ( for b4 being Point of b1 st b4 in b3 holds
b2 | b3 is_continuous_in b4 ) ) );

theorem Th25: :: NFCONT_1:25
for b1, b2 being RealNormSpace
for b3 being set
for b4 being PartFunc of b2,b1 holds
( b4 is_continuous_on b3 iff ( b3 c= dom b4 & ( for b5 being sequence of b2 st rng b5 c= b3 & b5 is convergent & lim b5 in b3 holds
( b4 * b5 is convergent & b4 /. (lim b5) = lim (b4 * b5) ) ) ) )
proof end;

theorem Th26: :: NFCONT_1:26
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b3,b2 holds
( b4 is_continuous_on b1 iff ( b1 c= dom b4 & ( for b5 being Point of b3
for b6 being Real st b5 in b1 & 0 < b6 holds
ex b7 being Real st
( 0 < b7 & ( for b8 being Point of b3 st b8 in b1 & ||.(b8 - b5).|| < b7 holds
||.((b4 /. b8) - (b4 /. b5)).|| < b6 ) ) ) ) )
proof end;

theorem Th27: :: NFCONT_1:27
for b1 being set
for b2 being RealNormSpace
for b3 being PartFunc of the carrier of b2, REAL holds
( b3 is_continuous_on b1 iff ( b1 c= dom b3 & ( for b4 being Point of b2
for b5 being Real st b4 in b1 & 0 < b5 holds
ex b6 being Real st
( 0 < b6 & ( for b7 being Point of b2 st b7 in b1 & ||.(b7 - b4).|| < b6 holds
abs ((b3 /. b7) - (b3 /. b4)) < b5 ) ) ) ) )
proof end;

theorem Th28: :: NFCONT_1:28
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 holds
( b4 is_continuous_on b1 iff b4 | b1 is_continuous_on b1 )
proof end;

theorem Th29: :: NFCONT_1:29
for b1 being set
for b2 being RealNormSpace
for b3 being PartFunc of the carrier of b2, REAL holds
( b3 is_continuous_on b1 iff b3 | b1 is_continuous_on b1 )
proof end;

theorem Th30: :: NFCONT_1:30
for b1, b2 being set
for b3, b4 being RealNormSpace
for b5 being PartFunc of b3,b4 st b5 is_continuous_on b1 & b2 c= b1 holds
b5 is_continuous_on b2
proof end;

theorem Th31: :: NFCONT_1:31
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Point of b2 st b4 in dom b3 holds
b3 is_continuous_on {b4}
proof end;

theorem Th32: :: NFCONT_1:32
for b1, b2 being RealNormSpace
for b3 being set
for b4, b5 being PartFunc of b2,b1 st b4 is_continuous_on b3 & b5 is_continuous_on b3 holds
( b4 + b5 is_continuous_on b3 & b4 - b5 is_continuous_on b3 )
proof end;

theorem Th33: :: NFCONT_1:33
for b1, b2 being RealNormSpace
for b3, b4 being set
for b5, b6 being PartFunc of b2,b1 st b5 is_continuous_on b3 & b6 is_continuous_on b4 holds
( b5 + b6 is_continuous_on b3 /\ b4 & b5 - b6 is_continuous_on b3 /\ b4 )
proof end;

theorem Th34: :: NFCONT_1:34
for b1, b2 being RealNormSpace
for b3 being Real
for b4 being set
for b5 being PartFunc of b2,b1 st b5 is_continuous_on b4 holds
b3 (#) b5 is_continuous_on b4
proof end;

theorem Th35: :: NFCONT_1:35
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 st b4 is_continuous_on b1 holds
( ||.b4.|| is_continuous_on b1 & - b4 is_continuous_on b1 )
proof end;

theorem Th36: :: NFCONT_1:36
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1 st b3 is total & ( for b4, b5 being Point of b2 holds b3 /. (b4 + b5) = (b3 /. b4) + (b3 /. b5) ) & ex b4 being Point of b2 st b3 is_continuous_in b4 holds
b3 is_continuous_on the carrier of b2
proof end;

theorem Th37: :: NFCONT_1:37
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1 st dom b3 is compact & b3 is_continuous_on dom b3 holds
rng b3 is compact
proof end;

theorem Th38: :: NFCONT_1:38
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL st dom b2 is compact & b2 is_continuous_on dom b2 holds
rng b2 is compact
proof end;

theorem Th39: :: NFCONT_1:39
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Subset of b2 st b4 c= dom b3 & b4 is compact & b3 is_continuous_on b4 holds
b3 .: b4 is compact
proof end;

theorem Th40: :: NFCONT_1:40
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL st dom b2 <> {} & dom b2 is compact & b2 is_continuous_on dom b2 holds
ex b3, b4 being Point of b1 st
( b3 in dom b2 & b4 in dom b2 & b2 /. b3 = upper_bound (rng b2) & b2 /. b4 = lower_bound (rng b2) )
proof end;

theorem Th41: :: NFCONT_1:41
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1 st dom b3 <> {} & dom b3 is compact & b3 is_continuous_on dom b3 holds
ex b4, b5 being Point of b2 st
( b4 in dom b3 & b5 in dom b3 & ||.b3.|| /. b4 = upper_bound (rng ||.b3.||) & ||.b3.|| /. b5 = lower_bound (rng ||.b3.||) )
proof end;

theorem Th42: :: NFCONT_1:42
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 holds ||.b4.|| | b1 = ||.(b4 | b1).||
proof end;

theorem Th43: :: NFCONT_1:43
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1
for b4 being Subset of b2 st b4 <> {} & b4 c= dom b3 & b4 is compact & b3 is_continuous_on b4 holds
ex b5, b6 being Point of b2 st
( b5 in b4 & b6 in b4 & ||.b3.|| /. b5 = upper_bound (||.b3.|| .: b4) & ||.b3.|| /. b6 = lower_bound (||.b3.|| .: b4) )
proof end;

theorem Th44: :: NFCONT_1:44
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL
for b3 being Subset of b1 st b3 <> {} & b3 c= dom b2 & b3 is compact & b2 is_continuous_on b3 holds
ex b4, b5 being Point of b1 st
( b4 in b3 & b5 in b3 & b2 /. b4 = upper_bound (b2 .: b3) & b2 /. b5 = lower_bound (b2 .: b3) )
proof end;

definition
let c1, c2 be RealNormSpace;
let c3 be set ;
let c4 be PartFunc of c1,c2;
pred c4 is_Lipschitzian_on c3 means :Def13: :: NFCONT_1:def 13
( a3 c= dom a4 & ex b1 being Real st
( 0 < b1 & ( for b2, b3 being Point of a1 st b2 in a3 & b3 in a3 holds
||.((a4 /. b2) - (a4 /. b3)).|| <= b1 * ||.(b2 - b3).|| ) ) );
end;

:: deftheorem Def13 defines is_Lipschitzian_on NFCONT_1:def 13 :
for b1, b2 being RealNormSpace
for b3 being set
for b4 being PartFunc of b1,b2 holds
( b4 is_Lipschitzian_on b3 iff ( b3 c= dom b4 & ex b5 being Real st
( 0 < b5 & ( for b6, b7 being Point of b1 st b6 in b3 & b7 in b3 holds
||.((b4 /. b6) - (b4 /. b7)).|| <= b5 * ||.(b6 - b7).|| ) ) ) );

definition
let c1 be RealNormSpace;
let c2 be set ;
let c3 be PartFunc of the carrier of c1, REAL ;
pred c3 is_Lipschitzian_on c2 means :Def14: :: NFCONT_1:def 14
( a2 c= dom a3 & ex b1 being Real st
( 0 < b1 & ( for b2, b3 being Point of a1 st b2 in a2 & b3 in a2 holds
abs ((a3 /. b2) - (a3 /. b3)) <= b1 * ||.(b2 - b3).|| ) ) );
end;

:: deftheorem Def14 defines is_Lipschitzian_on NFCONT_1:def 14 :
for b1 being RealNormSpace
for b2 being set
for b3 being PartFunc of the carrier of b1, REAL holds
( b3 is_Lipschitzian_on b2 iff ( b2 c= dom b3 & ex b4 being Real st
( 0 < b4 & ( for b5, b6 being Point of b1 st b5 in b2 & b6 in b2 holds
abs ((b3 /. b5) - (b3 /. b6)) <= b4 * ||.(b5 - b6).|| ) ) ) );

theorem Th45: :: NFCONT_1:45
for b1, b2 being set
for b3, b4 being RealNormSpace
for b5 being PartFunc of b3,b4 st b5 is_Lipschitzian_on b1 & b2 c= b1 holds
b5 is_Lipschitzian_on b2
proof end;

theorem Th46: :: NFCONT_1:46
for b1, b2 being set
for b3, b4 being RealNormSpace
for b5, b6 being PartFunc of b3,b4 st b5 is_Lipschitzian_on b1 & b6 is_Lipschitzian_on b2 holds
b5 + b6 is_Lipschitzian_on b1 /\ b2
proof end;

theorem Th47: :: NFCONT_1:47
for b1, b2 being set
for b3, b4 being RealNormSpace
for b5, b6 being PartFunc of b3,b4 st b5 is_Lipschitzian_on b1 & b6 is_Lipschitzian_on b2 holds
b5 - b6 is_Lipschitzian_on b1 /\ b2
proof end;

theorem Th48: :: NFCONT_1:48
for b1 being set
for b2 being Real
for b3, b4 being RealNormSpace
for b5 being PartFunc of b3,b4 st b5 is_Lipschitzian_on b1 holds
b2 (#) b5 is_Lipschitzian_on b1
proof end;

theorem Th49: :: NFCONT_1:49
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 st b4 is_Lipschitzian_on b1 holds
( - b4 is_Lipschitzian_on b1 & ||.b4.|| is_Lipschitzian_on b1 )
proof end;

theorem Th50: :: NFCONT_1:50
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 st b1 c= dom b4 & b4 is_constant_on b1 holds
b4 is_Lipschitzian_on b1
proof end;

theorem Th51: :: NFCONT_1:51
for b1 being RealNormSpace
for b2 being Subset of b1 holds id b2 is_Lipschitzian_on b2
proof end;

theorem Th52: :: NFCONT_1:52
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 st b4 is_Lipschitzian_on b1 holds
b4 is_continuous_on b1
proof end;

theorem Th53: :: NFCONT_1:53
for b1 being set
for b2 being RealNormSpace
for b3 being PartFunc of the carrier of b2, REAL st b3 is_Lipschitzian_on b1 holds
b3 is_continuous_on b1
proof end;

theorem Th54: :: NFCONT_1:54
for b1, b2 being RealNormSpace
for b3 being PartFunc of b2,b1 st ex b4 being Point of b1 st rng b3 = {b4} holds
b3 is_continuous_on dom b3
proof end;

theorem Th55: :: NFCONT_1:55
for b1 being set
for b2, b3 being RealNormSpace
for b4 being PartFunc of b2,b3 st b1 c= dom b4 & b4 is_constant_on b1 holds
b4 is_continuous_on b1
proof end;

theorem Th56: :: NFCONT_1:56
for b1 being RealNormSpace
for b2 being PartFunc of b1,b1 st ( for b3 being Point of b1 st b3 in dom b2 holds
b2 /. b3 = b3 ) holds
b2 is_continuous_on dom b2
proof end;

theorem Th57: :: NFCONT_1:57
for b1 being RealNormSpace
for b2 being PartFunc of b1,b1 st b2 = id (dom b2) holds
b2 is_continuous_on dom b2
proof end;

theorem Th58: :: NFCONT_1:58
for b1 being RealNormSpace
for b2 being Subset of b1
for b3 being PartFunc of b1,b1 st b2 c= dom b3 & b3 | b2 = id b2 holds
b3 is_continuous_on b2
proof end;

theorem Th59: :: NFCONT_1:59
for b1 being set
for b2 being RealNormSpace
for b3 being PartFunc of b2,b2
for b4 being Real
for b5 being Point of b2 st b1 c= dom b3 & ( for b6 being Point of b2 st b6 in b1 holds
b3 /. b6 = (b4 * b6) + b5 ) holds
b3 is_continuous_on b1
proof end;

theorem Th60: :: NFCONT_1:60
for b1 being RealNormSpace
for b2 being PartFunc of the carrier of b1, REAL st ( for b3 being Point of b1 st b3 in dom b2 holds
b2 /. b3 = ||.b3.|| ) holds
b2 is_continuous_on dom b2
proof end;

theorem Th61: :: NFCONT_1:61
for b1 being set
for b2 being RealNormSpace
for b3 being PartFunc of the carrier of b2, REAL st b1 c= dom b3 & ( for b4 being Point of b2 st b4 in b1 holds
b3 /. b4 = ||.b4.|| ) holds
b3 is_continuous_on b1
proof end;