Metamath Proof Explorer


Theorem bj-hbalt

Description: Closed form of hbal . When in main part, prove hbal and hbald from it. (Contributed by BJ, 2-May-2019)

Ref Expression
Assertion bj-hbalt
|- ( A. y ( ph -> A. x ph ) -> ( A. y ph -> A. x A. y ph ) )

Proof

Step Hyp Ref Expression
1 alim
 |-  ( A. y ( ph -> A. x ph ) -> ( A. y ph -> A. y A. x ph ) )
2 ax-11
 |-  ( A. y A. x ph -> A. x A. y ph )
3 1 2 syl6
 |-  ( A. y ( ph -> A. x ph ) -> ( A. y ph -> A. x A. y ph ) )