Theorem eximd

Description: Deduction form of Theorem 19.22 of Margaris p. 90, see exim . (Contributed by NM, 29-Jun-1993) (Revised by Mario Carneiro, 24-Sep-2016)

	Ref	Expression
Hypotheses	eximd.1	|- F/ x ph
	eximd.2	|- ( ph -> ( ps -> ch ) )
Assertion	eximd	|- ( ph -> ( E. x ps -> E. x ch ) )

Proof

Step	Hyp	Ref	Expression
1		eximd.1	|- F/ x ph
2		eximd.2	|- ( ph -> ( ps -> ch ) )
3	1	nf5ri	|- ( ph -> A. x ph )
4	3 2	eximdh	|- ( ph -> ( E. x ps -> E. x ch ) )