Theorem reximddv3

Description: Deduction from Theorem 19.22 of Margaris p. 90. (Contributed by Glauco Siliprandi, 5-Feb-2022)

	Ref	Expression
Hypotheses	reximddv3.1	|- ( ( ( ph /\ x e. A ) /\ ps ) -> ch )
	reximddv3.2	|- ( ph -> E. x e. A ps )
Assertion	reximddv3	|- ( ph -> E. x e. A ch )

Proof

Step	Hyp	Ref	Expression
1		reximddv3.1	|- ( ( ( ph /\ x e. A ) /\ ps ) -> ch )
2		reximddv3.2	|- ( ph -> E. x e. A ps )
3	1	anasss	|- ( ( ph /\ ( x e. A /\ ps ) ) -> ch )
4	3 2	reximddv	|- ( ph -> E. x e. A ch )