:: COMSEQ_1 semantic presentation

definition
mode Complex_Sequence is Function of NAT , COMPLEX ;
end;

theorem Th1: :: COMSEQ_1:1
for b1 being Function holds
( b1 is Complex_Sequence iff ( dom b1 = NAT & ( for b2 being set st b2 in NAT holds
b1 . b2 is Element of COMPLEX ) ) )
proof end;

theorem Th2: :: COMSEQ_1:2
for b1 being Function holds
( b1 is Complex_Sequence iff ( dom b1 = NAT & ( for b2 being Nat holds b1 . b2 is Element of COMPLEX ) ) )
proof end;

definition
let c1 be Complex_Sequence;
let c2 be Nat;
redefine func . as c1 . c2 -> Element of COMPLEX ;
coherence
c1 . c2 is Element of COMPLEX
by Th2;
end;

scheme :: COMSEQ_1:sch 1
s1{ F1( Nat) -> Element of COMPLEX } :
ex b1 being Complex_Sequence st
for b2 being Nat holds b1 . b2 = F1(b2)
proof end;

definition
let c1 be Complex_Sequence;
attr a1 is non-zero means :Def1: :: COMSEQ_1:def 1
rng a1 c= COMPLEX \ {0c };
end;

:: deftheorem Def1 defines non-zero COMSEQ_1:def 1 :
for b1 being Complex_Sequence holds
( b1 is non-zero iff rng b1 c= COMPLEX \ {0c } );

theorem Th3: :: COMSEQ_1:3
for b1 being Complex_Sequence holds
( b1 is non-zero iff for b2 being set st b2 in NAT holds
b1 . b2 <> 0c )
proof end;

registration
cluster non-zero Relation of NAT , COMPLEX ;
existence
ex b1 being Complex_Sequence st b1 is non-zero
proof end;
end;

theorem Th4: :: COMSEQ_1:4
for b1 being Complex_Sequence holds
( b1 is non-zero iff for b2 being Nat holds b1 . b2 <> 0c )
proof end;

theorem Th5: :: COMSEQ_1:5
canceled;

theorem Th6: :: COMSEQ_1:6
for b1, b2 being Complex_Sequence st ( for b3 being Nat holds b1 . b3 = b2 . b3 ) holds
b1 = b2
proof end;

theorem Th7: :: COMSEQ_1:7
for b1 being Element of COMPLEX ex b2 being Complex_Sequence st rng b2 = {b1}
proof end;

definition
let c1 be non empty set ;
let c2, c3 be PartFunc of c1, COMPLEX ;
deffunc H1( set ) -> Element of COMPLEX = (c2 /. a1) + (c3 /. a1);
defpred S1[ set ] means a1 in (dom c2) /\ (dom c3);
set c4 = (dom c2) /\ (dom c3);
func c2 + c3 -> PartFunc of a1, COMPLEX means :Def2: :: COMSEQ_1:def 2
( dom a4 = (dom a2) /\ (dom a3) & ( for b1 being Element of a1 st b1 in dom a4 holds
a4 . b1 = (a2 /. b1) + (a3 /. b1) ) );
existence
ex b1 being PartFunc of c1, COMPLEX st
( dom b1 = (dom c2) /\ (dom c3) & ( for b2 being Element of c1 st b2 in dom b1 holds
b1 . b2 = (c2 /. b2) + (c3 /. b2) ) )
proof end;
uniqueness
for b1, b2 being PartFunc of c1, COMPLEX st dom b1 = (dom c2) /\ (dom c3) & ( for b3 being Element of c1 st b3 in dom b1 holds
b1 . b3 = (c2 /. b3) + (c3 /. b3) ) & dom b2 = (dom c2) /\ (dom c3) & ( for b3 being Element of c1 st b3 in dom b2 holds
b2 . b3 = (c2 /. b3) + (c3 /. b3) ) holds
b1 = b2
proof end;
commutativity
for b1, b2, b3 being PartFunc of c1, COMPLEX st dom b1 = (dom b2) /\ (dom b3) & ( for b4 being Element of c1 st b4 in dom b1 holds
b1 . b4 = (b2 /. b4) + (b3 /. b4) ) holds
( dom b1 = (dom b3) /\ (dom b2) & ( for b4 being Element of c1 st b4 in dom b1 holds
b1 . b4 = (b3 /. b4) + (b2 /. b4) ) )
;
deffunc H2( set ) -> Element of COMPLEX = (c2 /. a1) * (c3 /. a1);
func c2 (#) c3 -> PartFunc of a1, COMPLEX means :Def3: :: COMSEQ_1:def 3
( dom a4 = (dom a2) /\ (dom a3) & ( for b1 being Element of a1 st b1 in dom a4 holds
a4 . b1 = (a2 /. b1) * (a3 /. b1) ) );
existence
ex b1 being PartFunc of c1, COMPLEX st
( dom b1 = (dom c2) /\ (dom c3) & ( for b2 being Element of c1 st b2 in dom b1 holds
b1 . b2 = (c2 /. b2) * (c3 /. b2) ) )
proof end;
uniqueness
for b1, b2 being PartFunc of c1, COMPLEX st dom b1 = (dom c2) /\ (dom c3) & ( for b3 being Element of c1 st b3 in dom b1 holds
b1 . b3 = (c2 /. b3) * (c3 /. b3) ) & dom b2 = (dom c2) /\ (dom c3) & ( for b3 being Element of c1 st b3 in dom b2 holds
b2 . b3 = (c2 /. b3) * (c3 /. b3) ) holds
b1 = b2
proof end;
commutativity
for b1, b2, b3 being PartFunc of c1, COMPLEX st dom b1 = (dom b2) /\ (dom b3) & ( for b4 being Element of c1 st b4 in dom b1 holds
b1 . b4 = (b2 /. b4) * (b3 /. b4) ) holds
( dom b1 = (dom b3) /\ (dom b2) & ( for b4 being Element of c1 st b4 in dom b1 holds
b1 . b4 = (b3 /. b4) * (b2 /. b4) ) )
;
end;

:: deftheorem Def2 defines + COMSEQ_1:def 2 :
for b1 being non empty set
for b2, b3, b4 being PartFunc of b1, COMPLEX holds
( b4 = b2 + b3 iff ( dom b4 = (dom b2) /\ (dom b3) & ( for b5 being Element of b1 st b5 in dom b4 holds
b4 . b5 = (b2 /. b5) + (b3 /. b5) ) ) );

:: deftheorem Def3 defines (#) COMSEQ_1:def 3 :
for b1 being non empty set
for b2, b3, b4 being PartFunc of b1, COMPLEX holds
( b4 = b2 (#) b3 iff ( dom b4 = (dom b2) /\ (dom b3) & ( for b5 being Element of b1 st b5 in dom b4 holds
b4 . b5 = (b2 /. b5) * (b3 /. b5) ) ) );

definition
let c1 be non empty set ;
let c2, c3 be Function of c1, COMPLEX ;
redefine func c2 + c3 -> PartFunc of a1, COMPLEX means :Def4: :: COMSEQ_1:def 4
( dom a4 = a1 & ( for b1 being Element of a1 holds a4 . b1 = (a2 . b1) + (a3 . b1) ) );
compatibility
for b1 being PartFunc of c1, COMPLEX holds
( b1 = c2 + c3 iff ( dom b1 = c1 & ( for b2 being Element of c1 holds b1 . b2 = (c2 . b2) + (c3 . b2) ) ) )
proof end;
redefine func c2 (#) c3 -> PartFunc of a1, COMPLEX means :Def5: :: COMSEQ_1:def 5
( dom a4 = a1 & ( for b1 being Element of a1 holds a4 . b1 = (a2 . b1) * (a3 . b1) ) );
compatibility
for b1 being PartFunc of c1, COMPLEX holds
( b1 = c2 (#) c3 iff ( dom b1 = c1 & ( for b2 being Element of c1 holds b1 . b2 = (c2 . b2) * (c3 . b2) ) ) )
proof end;
end;

:: deftheorem Def4 defines + COMSEQ_1:def 4 :
for b1 being non empty set
for b2, b3 being Function of b1, COMPLEX
for b4 being PartFunc of b1, COMPLEX holds
( b4 = b2 + b3 iff ( dom b4 = b1 & ( for b5 being Element of b1 holds b4 . b5 = (b2 . b5) + (b3 . b5) ) ) );

:: deftheorem Def5 defines (#) COMSEQ_1:def 5 :
for b1 being non empty set
for b2, b3 being Function of b1, COMPLEX
for b4 being PartFunc of b1, COMPLEX holds
( b4 = b2 (#) b3 iff ( dom b4 = b1 & ( for b5 being Element of b1 holds b4 . b5 = (b2 . b5) * (b3 . b5) ) ) );

registration
let c1 be non empty set ;
let c2, c3 be Function of c1, COMPLEX ;
cluster a2 + a3 -> total ;
coherence
c2 + c3 is total
proof end;
cluster a2 (#) a3 -> total ;
coherence
c2 (#) c3 is total
proof end;
end;

definition
let c1 be non empty set ;
let c2 be PartFunc of c1, COMPLEX ;
let c3 be complex number ;
func c3 (#) c2 -> PartFunc of a1, COMPLEX means :Def6: :: COMSEQ_1:def 6
( dom a4 = dom a2 & ( for b1 being Element of a1 st b1 in dom a4 holds
a4 . b1 = a3 * (a2 /. b1) ) );
existence
ex b1 being PartFunc of c1, COMPLEX st
( dom b1 = dom c2 & ( for b2 being Element of c1 st b2 in dom b1 holds
b1 . b2 = c3 * (c2 /. b2) ) )
proof end;
uniqueness
for b1, b2 being PartFunc of c1, COMPLEX st dom b1 = dom c2 & ( for b3 being Element of c1 st b3 in dom b1 holds
b1 . b3 = c3 * (c2 /. b3) ) & dom b2 = dom c2 & ( for b3 being Element of c1 st b3 in dom b2 holds
b2 . b3 = c3 * (c2 /. b3) ) holds
b1 = b2
proof end;
end;

:: deftheorem Def6 defines (#) COMSEQ_1:def 6 :
for b1 being non empty set
for b2 being PartFunc of b1, COMPLEX
for b3 being complex number
for b4 being PartFunc of b1, COMPLEX holds
( b4 = b3 (#) b2 iff ( dom b4 = dom b2 & ( for b5 being Element of b1 st b5 in dom b4 holds
b4 . b5 = b3 * (b2 /. b5) ) ) );

definition
let c1 be non empty set ;
let c2 be Function of c1, COMPLEX ;
let c3 be complex number ;
redefine func c3 (#) c2 -> PartFunc of a1, COMPLEX means :Def7: :: COMSEQ_1:def 7
( dom a4 = a1 & ( for b1 being Element of a1 holds a4 . b1 = a3 * (a2 . b1) ) );
compatibility
for b1 being PartFunc of c1, COMPLEX holds
( b1 = c3 (#) c2 iff ( dom b1 = c1 & ( for b2 being Element of c1 holds b1 . b2 = c3 * (c2 . b2) ) ) )
proof end;
end;

:: deftheorem Def7 defines (#) COMSEQ_1:def 7 :
for b1 being non empty set
for b2 being Function of b1, COMPLEX
for b3 being complex number
for b4 being PartFunc of b1, COMPLEX holds
( b4 = b3 (#) b2 iff ( dom b4 = b1 & ( for b5 being Element of b1 holds b4 . b5 = b3 * (b2 . b5) ) ) );

registration
let c1 be non empty set ;
let c2 be Function of c1, COMPLEX ;
let c3 be complex number ;
cluster a3 (#) a2 -> total ;
coherence
c3 (#) c2 is total
proof end;
end;

definition
let c1 be non empty set ;
let c2 be PartFunc of c1, COMPLEX ;
deffunc H1( set ) -> Element of COMPLEX = - (c2 /. a1);
func - c2 -> PartFunc of a1, COMPLEX means :Def8: :: COMSEQ_1:def 8
( dom a3 = dom a2 & ( for b1 being Element of a1 st b1 in dom a3 holds
a3 . b1 = - (a2 /. b1) ) );
existence
ex b1 being PartFunc of c1, COMPLEX st
( dom b1 = dom c2 & ( for b2 being Element of c1 st b2 in dom b1 holds
b1 . b2 = - (c2 /. b2) ) )
proof end;
uniqueness
for b1, b2 being PartFunc of c1, COMPLEX st dom b1 = dom c2 & ( for b3 being Element of c1 st b3 in dom b1 holds
b1 . b3 = - (c2 /. b3) ) & dom b2 = dom c2 & ( for b3 being Element of c1 st b3 in dom b2 holds
b2 . b3 = - (c2 /. b3) ) holds
b1 = b2
proof end;
end;

:: deftheorem Def8 defines - COMSEQ_1:def 8 :
for b1 being non empty set
for b2, b3 being PartFunc of b1, COMPLEX holds
( b3 = - b2 iff ( dom b3 = dom b2 & ( for b4 being Element of b1 st b4 in dom b3 holds
b3 . b4 = - (b2 /. b4) ) ) );

definition
let c1 be non empty set ;
let c2 be Function of c1, COMPLEX ;
redefine func - c2 -> PartFunc of a1, COMPLEX means :Def9: :: COMSEQ_1:def 9
( dom a3 = a1 & ( for b1 being Element of a1 holds a3 . b1 = - (a2 . b1) ) );
compatibility
for b1 being PartFunc of c1, COMPLEX holds
( b1 = - c2 iff ( dom b1 = c1 & ( for b2 being Element of c1 holds b1 . b2 = - (c2 . b2) ) ) )
proof end;
end;

:: deftheorem Def9 defines - COMSEQ_1:def 9 :
for b1 being non empty set
for b2 being Function of b1, COMPLEX
for b3 being PartFunc of b1, COMPLEX holds
( b3 = - b2 iff ( dom b3 = b1 & ( for b4 being Element of b1 holds b3 . b4 = - (b2 . b4) ) ) );

registration
let c1 be non empty set ;
let c2 be Function of c1, COMPLEX ;
cluster - a2 -> total ;
coherence
- c2 is total
proof end;
end;

definition
let c1 be non empty set ;
let c2, c3 be PartFunc of c1, COMPLEX ;
func c2 - c3 -> PartFunc of a1, COMPLEX equals :: COMSEQ_1:def 10
a2 + (- a3);
correctness
coherence
c2 + (- c3) is PartFunc of c1, COMPLEX
;
;
end;

:: deftheorem Def10 defines - COMSEQ_1:def 10 :
for b1 being non empty set
for b2, b3 being PartFunc of b1, COMPLEX holds b2 - b3 = b2 + (- b3);

registration
let c1 be non empty set ;
let c2, c3 be Function of c1, COMPLEX ;
cluster a2 - a3 -> total ;
correctness
coherence
c2 - c3 is total
;
;
end;

definition
let c1 be Complex_Sequence;
func c1 " -> Complex_Sequence means :Def11: :: COMSEQ_1:def 11
for b1 being Nat holds a2 . b1 = (a1 . b1) " ;
existence
ex b1 being Complex_Sequence st
for b2 being Nat holds b1 . b2 = (c1 . b2) "
proof end;
uniqueness
for b1, b2 being Complex_Sequence st ( for b3 being Nat holds b1 . b3 = (c1 . b3) " ) & ( for b3 being Nat holds b2 . b3 = (c1 . b3) " ) holds
b1 = b2
proof end;
end;

:: deftheorem Def11 defines " COMSEQ_1:def 11 :
for b1, b2 being Complex_Sequence holds
( b2 = b1 " iff for b3 being Nat holds b2 . b3 = (b1 . b3) " );

definition
let c1, c2 be Complex_Sequence;
func c1 /" c2 -> Complex_Sequence equals :: COMSEQ_1:def 12
a1 (#) (a2 " );
correctness
coherence
c1 (#) (c2 " ) is Complex_Sequence
;
;
end;

:: deftheorem Def12 defines /" COMSEQ_1:def 12 :
for b1, b2 being Complex_Sequence holds b1 /" b2 = b1 (#) (b2 " );

definition
let c1 be non empty set ;
let c2 be PartFunc of c1, COMPLEX ;
deffunc H1( set ) -> Element of REAL = |.(c2 /. a1).|;
func |.c2.| -> PartFunc of a1, REAL means :Def13: :: COMSEQ_1:def 13
( dom a3 = dom a2 & ( for b1 being Element of a1 st b1 in dom a3 holds
a3 . b1 = |.(a2 /. b1).| ) );
existence
ex b1 being PartFunc of c1, REAL st
( dom b1 = dom c2 & ( for b2 being Element of c1 st b2 in dom b1 holds
b1 . b2 = |.(c2 /. b2).| ) )
proof end;
uniqueness
for b1, b2 being PartFunc of c1, REAL st dom b1 = dom c2 & ( for b3 being Element of c1 st b3 in dom b1 holds
b1 . b3 = |.(c2 /. b3).| ) & dom b2 = dom c2 & ( for b3 being Element of c1 st b3 in dom b2 holds
b2 . b3 = |.(c2 /. b3).| ) holds
b1 = b2
proof end;
end;

:: deftheorem Def13 defines |. COMSEQ_1:def 13 :
for b1 being non empty set
for b2 being PartFunc of b1, COMPLEX
for b3 being PartFunc of b1, REAL holds
( b3 = |.b2.| iff ( dom b3 = dom b2 & ( for b4 being Element of b1 st b4 in dom b3 holds
b3 . b4 = |.(b2 /. b4).| ) ) );

definition
let c1 be non empty set ;
let c2 be Function of c1, COMPLEX ;
redefine func |.c2.| -> PartFunc of a1, REAL means :Def14: :: COMSEQ_1:def 14
( dom a3 = a1 & ( for b1 being Element of a1 holds a3 . b1 = |.(a2 . b1).| ) );
compatibility
for b1 being PartFunc of c1, REAL holds
( b1 = |.c2.| iff ( dom b1 = c1 & ( for b2 being Element of c1 holds b1 . b2 = |.(c2 . b2).| ) ) )
proof end;
end;

:: deftheorem Def14 defines |. COMSEQ_1:def 14 :
for b1 being non empty set
for b2 being Function of b1, COMPLEX
for b3 being PartFunc of b1, REAL holds
( b3 = |.b2.| iff ( dom b3 = b1 & ( for b4 being Element of b1 holds b3 . b4 = |.(b2 . b4).| ) ) );

registration
let c1 be non empty set ;
let c2 be Function of c1, COMPLEX ;
cluster |.a2.| -> total ;
coherence
|.c2.| is total
proof end;
end;

theorem Th8: :: COMSEQ_1:8
canceled;

theorem Th9: :: COMSEQ_1:9
for b1, b2, b3 being Complex_Sequence holds (b1 + b2) + b3 = b1 + (b2 + b3)
proof end;

theorem Th10: :: COMSEQ_1:10
canceled;

theorem Th11: :: COMSEQ_1:11
for b1, b2, b3 being Complex_Sequence holds (b1 (#) b2) (#) b3 = b1 (#) (b2 (#) b3)
proof end;

theorem Th12: :: COMSEQ_1:12
for b1, b2, b3 being Complex_Sequence holds (b1 + b2) (#) b3 = (b1 (#) b3) + (b2 (#) b3)
proof end;

theorem Th13: :: COMSEQ_1:13
for b1, b2, b3 being Complex_Sequence holds b1 (#) (b2 + b3) = (b1 (#) b2) + (b1 (#) b3) by Th12;

theorem Th14: :: COMSEQ_1:14
for b1 being Complex_Sequence holds - b1 = (- 1r ) (#) b1
proof end;

theorem Th15: :: COMSEQ_1:15
for b1 being Element of COMPLEX
for b2, b3 being Complex_Sequence holds b1 (#) (b2 (#) b3) = (b1 (#) b2) (#) b3
proof end;

theorem Th16: :: COMSEQ_1:16
for b1 being Element of COMPLEX
for b2, b3 being Complex_Sequence holds b1 (#) (b2 (#) b3) = b2 (#) (b1 (#) b3)
proof end;

theorem Th17: :: COMSEQ_1:17
for b1, b2, b3 being Complex_Sequence holds (b1 - b2) (#) b3 = (b1 (#) b3) - (b2 (#) b3)
proof end;

theorem Th18: :: COMSEQ_1:18
for b1, b2, b3 being Complex_Sequence holds (b1 (#) b2) - (b1 (#) b3) = b1 (#) (b2 - b3) by Th17;

theorem Th19: :: COMSEQ_1:19
for b1 being Element of COMPLEX
for b2, b3 being Complex_Sequence holds b1 (#) (b2 + b3) = (b1 (#) b2) + (b1 (#) b3)
proof end;

theorem Th20: :: COMSEQ_1:20
for b1, b2 being Element of COMPLEX
for b3 being Complex_Sequence holds (b1 * b2) (#) b3 = b1 (#) (b2 (#) b3)
proof end;

theorem Th21: :: COMSEQ_1:21
for b1 being Element of COMPLEX
for b2, b3 being Complex_Sequence holds b1 (#) (b2 - b3) = (b1 (#) b2) - (b1 (#) b3)
proof end;

theorem Th22: :: COMSEQ_1:22
for b1 being Element of COMPLEX
for b2, b3 being Complex_Sequence holds b1 (#) (b2 /" b3) = (b1 (#) b2) /" b3 by Th15;

theorem Th23: :: COMSEQ_1:23
for b1, b2, b3 being Complex_Sequence holds b1 - (b2 + b3) = (b1 - b2) - b3
proof end;

theorem Th24: :: COMSEQ_1:24
for b1 being Complex_Sequence holds 1r (#) b1 = b1
proof end;

theorem Th25: :: COMSEQ_1:25
for b1 being Complex_Sequence holds - (- b1) = b1
proof end;

theorem Th26: :: COMSEQ_1:26
for b1, b2 being Complex_Sequence holds b1 - (- b2) = b1 + b2 by Th25;

theorem Th27: :: COMSEQ_1:27
for b1, b2, b3 being Complex_Sequence holds b1 - (b2 - b3) = (b1 - b2) + b3
proof end;

theorem Th28: :: COMSEQ_1:28
for b1, b2, b3 being Complex_Sequence holds b1 + (b2 - b3) = (b1 + b2) - b3 by Th9;

theorem Th29: :: COMSEQ_1:29
for b1, b2 being Complex_Sequence holds
( (- b1) (#) b2 = - (b1 (#) b2) & b1 (#) (- b2) = - (b1 (#) b2) )
proof end;

theorem Th30: :: COMSEQ_1:30
for b1 being Complex_Sequence st b1 is non-zero holds
b1 " is non-zero
proof end;

theorem Th31: :: COMSEQ_1:31
for b1 being Complex_Sequence holds (b1 " ) " = b1
proof end;

theorem Th32: :: COMSEQ_1:32
for b1, b2 being Complex_Sequence holds
( ( b1 is non-zero & b2 is non-zero ) iff b1 (#) b2 is non-zero )
proof end;

theorem Th33: :: COMSEQ_1:33
for b1, b2 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
(b1 " ) (#) (b2 " ) = (b1 (#) b2) "
proof end;

theorem Th34: :: COMSEQ_1:34
for b1, b2 being Complex_Sequence st b1 is non-zero holds
(b2 /" b1) (#) b1 = b2
proof end;

theorem Th35: :: COMSEQ_1:35
for b1, b2, b3, b4 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
(b3 /" b1) (#) (b4 /" b2) = (b3 (#) b4) /" (b1 (#) b2)
proof end;

theorem Th36: :: COMSEQ_1:36
for b1, b2 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
b1 /" b2 is non-zero
proof end;

theorem Th37: :: COMSEQ_1:37
for b1, b2 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
(b1 /" b2) " = b2 /" b1
proof end;

theorem Th38: :: COMSEQ_1:38
for b1, b2, b3 being Complex_Sequence holds b1 (#) (b2 /" b3) = (b1 (#) b2) /" b3 by Th11;

theorem Th39: :: COMSEQ_1:39
for b1, b2, b3 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
b3 /" (b1 /" b2) = (b3 (#) b2) /" b1
proof end;

theorem Th40: :: COMSEQ_1:40
for b1, b2, b3 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
b3 /" b1 = (b3 (#) b2) /" (b1 (#) b2)
proof end;

theorem Th41: :: COMSEQ_1:41
for b1 being Element of COMPLEX
for b2 being Complex_Sequence st b1 <> 0c & b2 is non-zero holds
b1 (#) b2 is non-zero
proof end;

theorem Th42: :: COMSEQ_1:42
for b1 being Complex_Sequence st b1 is non-zero holds
- b1 is non-zero
proof end;

theorem Th43: :: COMSEQ_1:43
for b1 being Element of COMPLEX
for b2 being Complex_Sequence st b1 <> 0c & b2 is non-zero holds
(b1 (#) b2) " = (b1 " ) (#) (b2 " )
proof end;

theorem Th44: :: COMSEQ_1:44
for b1 being Complex_Sequence st b1 is non-zero holds
(- b1) " = (- 1r ) (#) (b1 " )
proof end;

theorem Th45: :: COMSEQ_1:45
for b1, b2 being Complex_Sequence st b1 is non-zero holds
( - (b2 /" b1) = (- b2) /" b1 & b2 /" (- b1) = - (b2 /" b1) )
proof end;

theorem Th46: :: COMSEQ_1:46
for b1, b2, b3 being Complex_Sequence holds
( (b1 /" b2) + (b3 /" b2) = (b1 + b3) /" b2 & (b1 /" b2) - (b3 /" b2) = (b1 - b3) /" b2 ) by Th12, Th17;

theorem Th47: :: COMSEQ_1:47
for b1, b2, b3, b4 being Complex_Sequence st b1 is non-zero & b2 is non-zero holds
( (b3 /" b1) + (b4 /" b2) = ((b3 (#) b2) + (b4 (#) b1)) /" (b1 (#) b2) & (b3 /" b1) - (b4 /" b2) = ((b3 (#) b2) - (b4 (#) b1)) /" (b1 (#) b2) )
proof end;

theorem Th48: :: COMSEQ_1:48
for b1, b2, b3, b4 being Complex_Sequence st b1 is non-zero & b2 is non-zero & b3 is non-zero holds
(b4 /" b1) /" (b2 /" b3) = (b4 (#) b3) /" (b1 (#) b2)
proof end;

theorem Th49: :: COMSEQ_1:49
for b1, b2 being Complex_Sequence holds |.(b1 (#) b2).| = |.b1.| (#) |.b2.|
proof end;

theorem Th50: :: COMSEQ_1:50
for b1 being Complex_Sequence st b1 is non-zero holds
|.b1.| is_not_0
proof end;

theorem Th51: :: COMSEQ_1:51
for b1 being Complex_Sequence holds |.b1.| " = |.(b1 " ).|
proof end;

theorem Th52: :: COMSEQ_1:52
for b1, b2 being Complex_Sequence holds |.(b1 /" b2).| = |.b1.| /" |.b2.|
proof end;

theorem Th53: :: COMSEQ_1:53
for b1 being Element of COMPLEX
for b2 being Complex_Sequence holds |.(b1 (#) b2).| = |.b1.| (#) |.b2.|
proof end;