Metamath Proof Explorer


Theorem bnj1350

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

Ref Expression
Hypothesis bnj1350.1 χ x χ
Assertion bnj1350 φ ψ χ x φ ψ χ

Proof

Step Hyp Ref Expression
1 bnj1350.1 χ x χ
2 ax-5 φ x φ
3 ax-5 ψ x ψ
4 2 3 1 hb3an φ ψ χ x φ ψ χ