Theorem bj-cbvexivw

Description: Change bound variable. This is to cbvexvw what cbvalivw is to cbvalvw . TODO: move after cbvalivw . (Contributed by BJ, 17-Mar-2020)

	Ref	Expression
Hypothesis	bj-cbvexivw.1	|- ( y = x -> ( ph -> ps ) )
Assertion	bj-cbvexivw	|- ( E. x ph -> E. y ps )

Proof

Step	Hyp	Ref	Expression
1		bj-cbvexivw.1	|- ( y = x -> ( ph -> ps ) )
2		ax5e	|- ( E. x E. y ps -> E. y ps )
3		ax-5	|- ( ph -> A. y ph )
4	2 3 1	bj-cbvexiw	|- ( E. x ph -> E. y ps )