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Theorem ralcomf 2595
Description: Commutation of restricted quantifiers. (Contributed by Mario Carneiro, 14-Oct-2016.)
Hypotheses
Ref Expression
ralcomf.1 𝑦𝐴
ralcomf.2 𝑥𝐵
Assertion
Ref Expression
ralcomf (∀𝑥𝐴𝑦𝐵 𝜑 ↔ ∀𝑦𝐵𝑥𝐴 𝜑)
Distinct variable group:   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑥,𝑦)   𝐴(𝑥,𝑦)   𝐵(𝑥,𝑦)

Proof of Theorem ralcomf
StepHypRef Expression
1 ancomsimp 1417 . . . 4 (((𝑥𝐴𝑦𝐵) → 𝜑) ↔ ((𝑦𝐵𝑥𝐴) → 𝜑))
212albii 1448 . . 3 (∀𝑥𝑦((𝑥𝐴𝑦𝐵) → 𝜑) ↔ ∀𝑥𝑦((𝑦𝐵𝑥𝐴) → 𝜑))
3 alcom 1455 . . 3 (∀𝑥𝑦((𝑦𝐵𝑥𝐴) → 𝜑) ↔ ∀𝑦𝑥((𝑦𝐵𝑥𝐴) → 𝜑))
42, 3bitri 183 . 2 (∀𝑥𝑦((𝑥𝐴𝑦𝐵) → 𝜑) ↔ ∀𝑦𝑥((𝑦𝐵𝑥𝐴) → 𝜑))
5 ralcomf.1 . . 3 𝑦𝐴
65r2alf 2455 . 2 (∀𝑥𝐴𝑦𝐵 𝜑 ↔ ∀𝑥𝑦((𝑥𝐴𝑦𝐵) → 𝜑))
7 ralcomf.2 . . 3 𝑥𝐵
87r2alf 2455 . 2 (∀𝑦𝐵𝑥𝐴 𝜑 ↔ ∀𝑦𝑥((𝑦𝐵𝑥𝐴) → 𝜑))
94, 6, 83bitr4i 211 1 (∀𝑥𝐴𝑦𝐵 𝜑 ↔ ∀𝑦𝐵𝑥𝐴 𝜑)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 103  wb 104  wal 1330  wcel 1481  wnfc 2269  wral 2417
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1424  ax-7 1425  ax-gen 1426  ax-ie1 1470  ax-ie2 1471  ax-8 1483  ax-10 1484  ax-11 1485  ax-i12 1486  ax-bndl 1487  ax-4 1488  ax-17 1507  ax-i9 1511  ax-ial 1515  ax-i5r 1516  ax-ext 2122
This theorem depends on definitions:  df-bi 116  df-nf 1438  df-sb 1737  df-cleq 2133  df-clel 2136  df-nfc 2271  df-ral 2422
This theorem is referenced by:  ralcom  2597  ssiinf  3870
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