Metamath Proof Explorer


Theorem bnj1517

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypothesis bnj1517.1 A = x | φ ψ
Assertion bnj1517 x A ψ

Proof

Step Hyp Ref Expression
1 bnj1517.1 A = x | φ ψ
2 1 bnj1436 x A φ ψ
3 2 simprd x A ψ