Metamath Proof Explorer


Theorem cbvsbcdavw2

Description: Change bound variable of a class substitution. General version of cbvsbcdavw . Deduction form. (Contributed by GG, 14-Aug-2025)

Ref Expression
Hypotheses cbvsbcdavw2.1
|- ( ph -> A = B )
cbvsbcdavw2.2
|- ( ( ph /\ x = y ) -> ( ps <-> ch ) )
Assertion cbvsbcdavw2
|- ( ph -> ( [. A / x ]. ps <-> [. B / y ]. ch ) )

Proof

Step Hyp Ref Expression
1 cbvsbcdavw2.1
 |-  ( ph -> A = B )
2 cbvsbcdavw2.2
 |-  ( ( ph /\ x = y ) -> ( ps <-> ch ) )
3 2 cbvabdavw
 |-  ( ph -> { x | ps } = { y | ch } )
4 1 3 eleq12d
 |-  ( ph -> ( A e. { x | ps } <-> B e. { y | ch } ) )
5 df-sbc
 |-  ( [. A / x ]. ps <-> A e. { x | ps } )
6 df-sbc
 |-  ( [. B / y ]. ch <-> B e. { y | ch } )
7 4 5 6 3bitr4g
 |-  ( ph -> ( [. A / x ]. ps <-> [. B / y ]. ch ) )