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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 697 | . . 3 ⊢ ((𝑥 ∈ 𝐴 → ¬ 𝜑) ↔ ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) | |
| 2 | 1 | albii 1519 | . 2 ⊢ (∀𝑥(𝑥 ∈ 𝐴 → ¬ 𝜑) ↔ ∀𝑥 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 3 | df-ral 2527 | . 2 ⊢ (∀𝑥 ∈ 𝐴 ¬ 𝜑 ↔ ∀𝑥(𝑥 ∈ 𝐴 → ¬ 𝜑)) | |
| 4 | sbn 2008 | . . . 4 ⊢ ([𝑦 / 𝑥] ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) | |
| 5 | 4 | albii 1519 | . . 3 ⊢ (∀𝑦[𝑦 / 𝑥] ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∀𝑦 ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 6 | nfv 1577 | . . . 4 ⊢ Ⅎ𝑦 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) | |
| 7 | 6 | sb8 1905 | . . 3 ⊢ (∀𝑥 ¬ (𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∀𝑦[𝑦 / 𝑥] ¬ (𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 8 | eq0 3531 | . . . 4 ⊢ ({𝑥 ∈ 𝐴 ∣ 𝜑} = ∅ ↔ ∀𝑦 ¬ 𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑}) | |
| 9 | df-rab 2531 | . . . . . . . 8 ⊢ {𝑥 ∈ 𝐴 ∣ 𝜑} = {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} | |
| 10 | 9 | eleq2i 2301 | . . . . . . 7 ⊢ (𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑} ↔ 𝑦 ∈ {𝑥 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)}) |
| 11 | df-clab 2221 | . . . . . . 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 674 | . . . . 5 ⊢ (¬ 𝑦 ∈ {𝑥 ∈ 𝐴 ∣ 𝜑} ↔ ¬ [𝑦 / 𝑥](𝑥 ∈ 𝐴 ∧ 𝜑)) |
| 14 | 13 | albii 1519 | . . . 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 1396 = wceq 1398 [wsb 1811 ∈ wcel 2205 {cab 2220 ∀wral 2522 {crab 2526 ∅c0 3512 |
| 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 619 ax-in2 620 ax-io 717 ax-5 1496 ax-7 1497 ax-gen 1498 ax-ie1 1542 ax-ie2 1543 ax-8 1553 ax-10 1554 ax-11 1555 ax-i12 1556 ax-bndl 1558 ax-4 1559 ax-17 1575 ax-i9 1579 ax-ial 1583 ax-i5r 1584 ax-ext 2216 |
| This theorem depends on definitions: df-bi 117 df-tru 1401 df-fal 1404 df-nf 1510 df-sb 1812 df-clab 2221 df-cleq 2227 df-clel 2230 df-nfc 2375 df-ral 2527 df-rab 2531 df-v 2817 df-dif 3216 df-nul 3513 |
| This theorem is referenced by: rabnc 3545 rabrsndc 3764 exmidsssnc 4321 ssfilem 7143 ssfilemd 7145 diffitest 7157 ssfirab 7210 ctssexmid 7454 exmidonfinlem 7509 iooidg 10261 icc0r 10278 fznlem 10395 ioo0 10643 ico0 10645 ioc0 10646 sshashneg 11230 hashfibclem 11231 hashfibc 11232 phiprmpw 12944 hashgcdeq 12962 unennn 13232 znnen 13233 fczpsrbag 14946 lgsquadlem2 16077 pw0ss 16204 umgrnloop0 16238 lfgrnloopen 16254 vtxd0nedgbfi 16420 clwwlkn0 16529 eupth2lembfi 16598 |
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