:: XCMPLX_0 semantic presentation :: Showing IDV graph ... (Click the Palm Trees again to close it)
Lm1: one =
succ 0
by ORDINAL2:def 4
.=
1
;
:: deftheorem defines <i> XCMPLX_0:def 1 :
:: deftheorem Def2 defines complex XCMPLX_0:def 2 :
:: deftheorem defines zero XCMPLX_0:def 3 :
definition
let x,
y be
complex number ;
x in COMPLEX
by Def2;
then consider x1,
x2 being
Element of
REAL such that A1:
x = [*x1,x2*]
by ARYTM_0:11;
y in COMPLEX
by Def2;
then consider y1,
y2 being
Element of
REAL such that A2:
y = [*y1,y2*]
by ARYTM_0:11;
func x + y -> set means :
Def4:
:: XCMPLX_0:def 4
ex
x1,
x2,
y1,
y2 being
Element of
REAL st
(
x = [*x1,x2*] &
y = [*y1,y2*] &
it = [*(+ x1,y1),(+ x2,y2)*] );
existence
ex b1 being set ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b1 = [*(+ x1,y1),(+ x2,y2)*] )
uniqueness
for b1, b2 being set st ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b1 = [*(+ x1,y1),(+ x2,y2)*] ) & ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b2 = [*(+ x1,y1),(+ x2,y2)*] ) holds
b1 = b2
commutativity
for b1 being set
for x, y being complex number st ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b1 = [*(+ x1,y1),(+ x2,y2)*] ) holds
ex x1, x2, y1, y2 being Element of REAL st
( y = [*x1,x2*] & x = [*y1,y2*] & b1 = [*(+ x1,y1),(+ x2,y2)*] )
;
func x * y -> set means :
Def5:
:: XCMPLX_0:def 5
ex
x1,
x2,
y1,
y2 being
Element of
REAL st
(
x = [*x1,x2*] &
y = [*y1,y2*] &
it = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] );
existence
ex b1 being set ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b1 = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] )
uniqueness
for b1, b2 being set st ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b1 = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] ) & ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b2 = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] ) holds
b1 = b2
commutativity
for b1 being set
for x, y being complex number st ex x1, x2, y1, y2 being Element of REAL st
( x = [*x1,x2*] & y = [*y1,y2*] & b1 = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] ) holds
ex x1, x2, y1, y2 being Element of REAL st
( y = [*x1,x2*] & x = [*y1,y2*] & b1 = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] )
;
end;
:: deftheorem Def4 defines + XCMPLX_0:def 4 :
:: deftheorem Def5 defines * XCMPLX_0:def 5 :
for
x,
y being
complex number for
b3 being
set holds
(
b3 = x * y iff ex
x1,
x2,
y1,
y2 being
Element of
REAL st
(
x = [*x1,x2*] &
y = [*y1,y2*] &
b3 = [*(+ (* x1,y1),(opp (* x2,y2))),(+ (* x1,y2),(* x2,y1))*] ) );
Lm2:
0 = [*0,0*]
by ARYTM_0:def 7;
reconsider j = one as Element of REAL by ARYTM_0:1, ARYTM_2:21;
Lm3:
for x, y, z being Element of REAL st + x,y = 0 & + x,z = 0 holds
y = z
:: deftheorem Def6 defines - XCMPLX_0:def 6 :
:: deftheorem Def7 defines " XCMPLX_0:def 7 :
for
z,
b2 being
complex number holds
( (
z <> 0 implies (
b2 = z " iff
z * b2 = 1 ) ) & ( not
z <> 0 implies (
b2 = z " iff
b2 = 0 ) ) );
:: deftheorem defines - XCMPLX_0:def 8 :
:: deftheorem defines / XCMPLX_0:def 9 :
Lm4:
for x, y, z being complex number holds x * (y * z) = (x * y) * z
Lm5:
REAL c= COMPLEX
by NUMBERS:def 2, XBOOLE_1:7;