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| Mirrors > Home > ILE Home > Th. List > rabeq0 | GIF version | ||
| Description: Condition for a restricted class abstraction to be empty. (Contributed by Jeff Madsen, 7-Jun-2010.) |
| Ref | Expression |
|---|---|
| rabeq0 | ⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} = ∅ ↔ ∀𝑥 ∈ 𝐴 ¬ 𝜑) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | imnan 694 | . . 3 ⊢ ((𝑥 ∈ 𝐴 → ¬ 𝜑) ↔ ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) | |
| 2 | 1 | albii 1516 | . 2 ⊢ (∀𝑥(𝑥 ∈ 𝐴 → ¬ 𝜑) ↔ ∀𝑥 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 3 | df-ral 2513 | . 2 ⊢ (∀𝑥 ∈ 𝐴 ¬ 𝜑 ↔ ∀𝑥(𝑥 ∈ 𝐴 → ¬ 𝜑)) | |
| 4 | sbn 2003 | . . . 4 ⊢ ([𝑦 / 𝑥] ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) | |
| 5 | 4 | albii 1516 | . . 3 ⊢ (∀𝑦[𝑦 / 𝑥] ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∀𝑦 ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 6 | nfv 1574 | . . . 4 ⊢ Ⅎ𝑦 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) | |
| 7 | 6 | sb8 1902 | . . 3 ⊢ (∀𝑥 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∀𝑦[𝑦 / 𝑥] ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 8 | eq0 3510 | . . . 4 ⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} = ∅ ↔ ∀𝑦 ¬ 𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑}) | |
| 9 | df-rab 2517 | . . . . . . . 8 ⊢ {𝑥 ∈ 𝐴 ∣ 𝜑} = {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} | |
| 10 | 9 | eleq2i 2296 | . . . . . . 7 ⊢ (𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑} ↔ 𝑦 ∈ {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)}) |
| 11 | df-clab 2216 | . . . . . . 7 ⊢ (𝑦 ∈ {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} ↔ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) | |
| 12 | 10, 11 | bitri 184 | . . . . . 6 ⊢ (𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑} ↔ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 13 | 12 | notbii 672 | . . . . 5 ⊢ (¬ 𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑} ↔ ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 14 | 13 | albii 1516 | . . . 4 ⊢ (∀𝑦 ¬ 𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑} ↔ ∀𝑦 ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 15 | 8, 14 | bitri 184 | . . 3 ⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} = ∅ ↔ ∀𝑦 ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 16 | 5, 7, 15 | 3bitr4ri 213 | . 2 ⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} = ∅ ↔ ∀𝑥 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 17 | 2, 3, 16 | 3bitr4ri 213 | 1 ⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} = ∅ ↔ ∀𝑥 ∈ 𝐴 ¬ 𝜑) |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 → wi 4 ∧ wa 104 ↔ wb 105 ∀wal 1393 = wceq 1395 [wsb 1808 ∈ wcel 2200 {cab 2215 ∀wral 2508 {crab 2512 ∅c0 3491 |
| 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-in1 617 ax-in2 618 ax-io 714 ax-5 1493 ax-7 1494 ax-gen 1495 ax-ie1 1539 ax-ie2 1540 ax-8 1550 ax-10 1551 ax-11 1552 ax-i12 1553 ax-bndl 1555 ax-4 1556 ax-17 1572 ax-i9 1576 ax-ial 1580 ax-i5r 1581 ax-ext 2211 |
| This theorem depends on definitions: df-bi 117 df-tru 1398 df-fal 1401 df-nf 1507 df-sb 1809 df-clab 2216 df-cleq 2222 df-clel 2225 df-nfc 2361 df-ral 2513 df-rab 2517 df-v 2801 df-dif 3199 df-nul 3492 |
| This theorem is referenced by: rabnc 3524 rabrsndc 3734 exmidsssnc 4287 ssfilem 7045 diffitest 7057 ssfirab 7106 ctssexmid 7325 exmidonfinlem 7379 iooidg 10113 icc0r 10130 fznlem 10245 ioo0 10487 ico0 10489 ioc0 10490 phiprmpw 12752 hashgcdeq 12770 unennn 12976 znnen 12977 fczpsrbag 14643 lgsquadlem2 15765 pw0ss 15891 umgrnloop0 15925 lfgrnloopen 15939 |
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