Metamath Proof Explorer


Theorem isoeq2

Description: Equality theorem for isomorphisms. (Contributed by NM, 17-May-2004)

Ref Expression
Assertion isoeq2 R = T H Isom R , S A B H Isom T , S A B

Proof

Step Hyp Ref Expression
1 breq R = T x R y x T y
2 1 bibi1d R = T x R y H x S H y x T y H x S H y
3 2 2ralbidv R = T x A y A x R y H x S H y x A y A x T y H x S H y
4 3 anbi2d R = T H : A 1-1 onto B x A y A x R y H x S H y H : A 1-1 onto B x A y A x T y H x S H y
5 df-isom H Isom R , S A B H : A 1-1 onto B x A y A x R y H x S H y
6 df-isom H Isom T , S A B H : A 1-1 onto B x A y A x T y H x S H y
7 4 5 6 3bitr4g R = T H Isom R , S A B H Isom T , S A B