Metamath Proof Explorer


Theorem r19.40

Description: Restricted quantifier version of Theorem 19.40 of Margaris p. 90. (Contributed by NM, 2-Apr-2004)

Ref Expression
Assertion r19.40 x A φ ψ x A φ x A ψ

Proof

Step Hyp Ref Expression
1 simpl φ ψ φ
2 1 reximi x A φ ψ x A φ
3 simpr φ ψ ψ
4 3 reximi x A φ ψ x A ψ
5 2 4 jca x A φ ψ x A φ x A ψ