Theorem exlimdvv

Description: Deduction form of Theorem 19.23 of Margaris p. 90, see 19.23 . (Contributed by NM, 31-Jul-1995)

	Ref	Expression
Hypothesis	exlimdvv.1	|- ( ph -> ( ps -> ch ) )
Assertion	exlimdvv	|- ( ph -> ( E. x E. y ps -> ch ) )

Proof

Step	Hyp	Ref	Expression
1		exlimdvv.1	|- ( ph -> ( ps -> ch ) )
2	1	exlimdv	|- ( ph -> ( E. y ps -> ch ) )
3	2	exlimdv	|- ( ph -> ( E. x E. y ps -> ch ) )