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| Mirrors > Home > ILE Home > Th. List > ralcomf | GIF version | ||
| Description: Commutation of restricted quantifiers. (Contributed by Mario Carneiro, 14-Oct-2016.) | 
| Ref | Expression | 
|---|---|
| ralcomf.1 | ⊢ Ⅎ𝑦𝐴 | 
| ralcomf.2 | ⊢ Ⅎ𝑥𝐵 | 
| Ref | Expression | 
|---|---|
| ralcomf | ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑦 ∈ 𝐵 ∀𝑥 ∈ 𝐴 𝜑) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | ancomsimp 1451 | . . . 4 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑) ↔ ((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑)) | |
| 2 | 1 | 2albii 1485 | . . 3 ⊢ (∀𝑥∀𝑦((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑) ↔ ∀𝑥∀𝑦((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑)) | 
| 3 | alcom 1492 | . . 3 ⊢ (∀𝑥∀𝑦((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑) ↔ ∀𝑦∀𝑥((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑)) | |
| 4 | 2, 3 | bitri 184 | . 2 ⊢ (∀𝑥∀𝑦((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑) ↔ ∀𝑦∀𝑥((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑)) | 
| 5 | ralcomf.1 | . . 3 ⊢ Ⅎ𝑦𝐴 | |
| 6 | 5 | r2alf 2514 | . 2 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑥∀𝑦((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 𝜑)) | 
| 7 | ralcomf.2 | . . 3 ⊢ Ⅎ𝑥𝐵 | |
| 8 | 7 | r2alf 2514 | . 2 ⊢ (∀𝑦 ∈ 𝐵 ∀𝑥 ∈ 𝐴 𝜑 ↔ ∀𝑦∀𝑥((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ 𝐴) → 𝜑)) | 
| 9 | 4, 6, 8 | 3bitr4i 212 | 1 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑦 ∈ 𝐵 ∀𝑥 ∈ 𝐴 𝜑) | 
| Colors of variables: wff set class | 
| Syntax hints: → wi 4 ∧ wa 104 ↔ wb 105 ∀wal 1362 ∈ wcel 2167 Ⅎwnfc 2326 ∀wral 2475 | 
| 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-io 710 ax-5 1461 ax-7 1462 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-8 1518 ax-10 1519 ax-11 1520 ax-i12 1521 ax-bndl 1523 ax-4 1524 ax-17 1540 ax-i9 1544 ax-ial 1548 ax-i5r 1549 ax-ext 2178 | 
| This theorem depends on definitions: df-bi 117 df-nf 1475 df-sb 1777 df-cleq 2189 df-clel 2192 df-nfc 2328 df-ral 2480 | 
| This theorem is referenced by: ralcom 2660 ssiinf 3966 | 
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