Metamath Proof Explorer


Theorem tposmpo

Description: Transposition of a two-argument mapping. (Contributed by Mario Carneiro, 10-Sep-2015)

Ref Expression
Hypothesis tposmpo.1 F = x A , y B C
Assertion tposmpo tpos F = y B , x A C

Proof

Step Hyp Ref Expression
1 tposmpo.1 F = x A , y B C
2 df-mpo x A , y B C = x y z | x A y B z = C
3 ancom x A y B y B x A
4 3 anbi1i x A y B z = C y B x A z = C
5 4 oprabbii x y z | x A y B z = C = x y z | y B x A z = C
6 1 2 5 3eqtri F = x y z | y B x A z = C
7 6 tposoprab tpos F = y x z | y B x A z = C
8 df-mpo y B , x A C = y x z | y B x A z = C
9 7 8 eqtr4i tpos F = y B , x A C