NFE Home New Foundations Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  NFE Home  >  Th. List  >  ralbii2 GIF version

Theorem ralbii2 2642
Description: Inference adding different restricted universal quantifiers to each side of an equivalence. (Contributed by NM, 15-Aug-2005.)
Hypothesis
Ref Expression
ralbii2.1 ((x Aφ) ↔ (x Bψ))
Assertion
Ref Expression
ralbii2 (x A φx B ψ)

Proof of Theorem ralbii2
StepHypRef Expression
1 ralbii2.1 . . 3 ((x Aφ) ↔ (x Bψ))
21albii 1566 . 2 (x(x Aφ) ↔ x(x Bψ))
3 df-ral 2619 . 2 (x A φx(x Aφ))
4 df-ral 2619 . 2 (x B ψx(x Bψ))
52, 3, 43bitr4i 268 1 (x A φx B ψ)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 176  wal 1540   wcel 1710  wral 2614
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557
This theorem depends on definitions:  df-bi 177  df-ral 2619
This theorem is referenced by:  raleqbii  2644  ralbiia  2646  ralrab  2998
  Copyright terms: Public domain W3C validator