Theorem 2ralbii 2541

Description: Inference adding two restricted universal quantifiers to both sides of an equivalence. (Contributed by NM, 1-Aug-2004.)

Hypothesis

Ref	Expression
ralbii.1	⊢ (𝜑 ↔ 𝜓)

Assertion

Ref	Expression
2ralbii	⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜓)

Proof of Theorem 2ralbii

Step	Hyp	Ref	Expression
1		ralbii.1	. . 3 ⊢ (𝜑 ↔ 𝜓)
2	1	ralbii 2539	. 2 ⊢ (∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑦 ∈ 𝐵 𝜓)
3	2	ralbii 2539	1 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜓)

Syntax hints:   ↔ wb 105  ∀wral 2511

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1496  ax-gen 1498  ax-4 1559  ax-17 1575

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-ral 2516

This theorem is referenced by:  rmo4f  3005  ordsoexmid  4666  cnvsom  5287  fununi  5405  tpossym  6485  axpre-suploc  8165  issubm  13616  isbasis2g  14836  ivthdich  15444