Theorem ceqsexvOLD

Description: Obsolete version of ceqsexv as of 12-Oct-2024. (Contributed by NM, 2-Mar-1995) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypotheses	ceqsexvOLD.1	|- A e. _V
	ceqsexvOLD.2	|- ( x = A -> ( ph <-> ps ) )
Assertion	ceqsexvOLD	|- ( E. x ( x = A /\ ph ) <-> ps )

Proof

Step	Hyp	Ref	Expression
1		ceqsexvOLD.1	|- A e. _V
2		ceqsexvOLD.2	|- ( x = A -> ( ph <-> ps ) )
3		nfv	|- F/ x ps
4	3 1 2	ceqsex	|- ( E. x ( x = A /\ ph ) <-> ps )