Theorem ralcomf 3359

Description: Commutation of restricted universal quantifiers. (Contributed by Mario Carneiro, 14-Oct-2016.)

Hypotheses

Ref	Expression
ralcomf.1	⊢ Ⅎ𝑦𝐴
ralcomf.2	⊢ Ⅎ𝑥𝐵

Assertion

Ref	Expression
ralcomf	⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑦 ∈ 𝐵 ∀𝑥 ∈ 𝐴 𝜑)

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝜑(𝑥,𝑦)   𝐴(𝑥,𝑦)   𝐵(𝑥,𝑦)

Proof of Theorem ralcomf

Step	Hyp	Ref	Expression
1		ancomst 467	. . . 4 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑) ↔ ((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑))
2	1	2albii 1821	. . 3 ⊢ (∀𝑥∀𝑦((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑) ↔ ∀𝑥∀𝑦((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑))
3		alcom 2163	. . 3 ⊢ (∀𝑥∀𝑦((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑) ↔ ∀𝑦∀𝑥((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑))
4	2, 3	bitri 277	. 2 ⊢ (∀𝑥∀𝑦((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑) ↔ ∀𝑦∀𝑥((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑))
5		ralcomf.1	. . 3 ⊢ Ⅎ𝑦𝐴
6	5	r2alf 3224	. 2 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑥∀𝑦((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑))
7		ralcomf.2	. . 3 ⊢ Ⅎ𝑥𝐵
8	7	r2alf 3224	. 2 ⊢ (∀𝑦 ∈ 𝐵 ∀𝑥 ∈ 𝐴 𝜑 ↔ ∀𝑦∀𝑥((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑))
9	4, 6, 8	3bitr4i 305	1 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑦 ∈ 𝐵 ∀𝑥 ∈ 𝐴 𝜑)

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 398  ∀wal 1535   ∈ wcel 2114  Ⅎwnfc 2963  ∀wral 3140

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-10 2145  ax-11 2161  ax-12 2177

This theorem depends on definitions:  df-bi 209  df-an 399  df-ex 1781  df-nf 1785  df-sb 2070  df-clel 2895  df-nfc 2965  df-ral 3145

This theorem is referenced by:  ssiinf  4980  ralcom4f  30235