Metamath Proof Explorer


Theorem 2ralbidv

Description: Formula-building rule for restricted universal quantifiers (deduction form). (Contributed by NM, 28-Jan-2006) (Revised by Szymon Jaroszewicz, 16-Mar-2007)

Ref Expression
Hypothesis 2ralbidv.1
|- ( ph -> ( ps <-> ch ) )
Assertion 2ralbidv
|- ( ph -> ( A. x e. A A. y e. B ps <-> A. x e. A A. y e. B ch ) )

Proof

Step Hyp Ref Expression
1 2ralbidv.1
 |-  ( ph -> ( ps <-> ch ) )
2 1 ralbidv
 |-  ( ph -> ( A. y e. B ps <-> A. y e. B ch ) )
3 2 ralbidv
 |-  ( ph -> ( A. x e. A A. y e. B ps <-> A. x e. A A. y e. B ch ) )