let a, b be real number ; :: thesis: ( |[a,b]| . 1 = a & |[a,b]| . 2 = b )
thus |[a,b]| . 1 =
(1,2 --> a,b) . 1
by Th25
.=
a
by FUNCT_4:66
; :: thesis: |[a,b]| . 2 = b
thus |[a,b]| . 2 =
(1,2 --> a,b) . 2
by Th25
.=
b
by FUNCT_4:66
; :: thesis: verum