set Y = (Seg 2) --> REAL;
set Y1 = SubFin (((Seg 2) --> REAL),1);
set F = CarProd ((Seg 2) --> REAL);
thus
CarProd ((Seg 2) --> REAL) is Function of [:REAL,REAL:],(REAL 2)
by Th37, SRINGS_5:8; for s, t being object st s in REAL & t in REAL holds
(CarProd ((Seg 2) --> REAL)) . [s,t] = <*s,t*>
thus
for s, t being object st s in REAL & t in REAL holds
(CarProd ((Seg 2) --> REAL)) . [s,t] = <*s,t*>
verumproof
let s,
t be
object ;
( s in REAL & t in REAL implies (CarProd ((Seg 2) --> REAL)) . [s,t] = <*s,t*> )
assume A1:
(
s in REAL &
t in REAL )
;
(CarProd ((Seg 2) --> REAL)) . [s,t] = <*s,t*>
A2:
( 1
in Seg 1 & 1
in Seg 2 & 2
in Seg 2 )
;
A3:
SubFin (
((Seg 2) --> REAL),1)
= ((Seg 2) --> REAL) | 1
by MEASUR13:def 5;
then A4:
(SubFin (((Seg 2) --> REAL),1)) . 1
= ((Seg 2) --> REAL) . 1
by A2, FUNCT_1:49;
CarProduct (SubFin (((Seg 2) --> REAL),1)) = (((Seg 2) --> REAL) | 1) . 1
by A3, MEASUR13:def 3;
then A5:
CarProduct (SubFin (((Seg 2) --> REAL),1)) = REAL
by A3, A4, A2, FUNCOP_1:7;
SubFin (
((Seg 2) --> REAL),1)
= <*REAL*>
by A2, A3, A4, FUNCOP_1:7, FINSEQ_1:40;
then A6:
SubFin (
((Seg 2) --> REAL),1)
= 1
|-> REAL
by FINSEQ_2:59;
ElmFin (
((Seg 2) --> REAL),
(1 + 1))
= REAL
by Th37;
then
ex
u,
v being
FinSequence st
(
(CarProd (SubFin (((Seg 2) --> REAL),1))) . s = u &
<*t*> = v &
(CarProd ((Seg 2) --> REAL)) . (
s,
t)
= u ^ v )
by A5, A1, Th13;
hence
(CarProd ((Seg 2) --> REAL)) . [s,t] = <*s,t*>
by A1, A6, Th38;
verum
end;