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| Mirrors > Home > NFE Home > Th. List > complab | GIF version | ||
| Description: Complement of a class abstraction. (Contributed by SF, 12-Jan-2015.) |
| Ref | Expression |
|---|---|
| complab | ⊢ ∼ {x ∣ φ} = {x ∣ ¬ φ} |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-clab 2340 | . . . . 5 ⊢ (y ∈ {x ∣ φ} ↔ [y / x]φ) | |
| 2 | 1 | notbii 287 | . . . 4 ⊢ (¬ y ∈ {x ∣ φ} ↔ ¬ [y / x]φ) |
| 3 | sbn 2062 | . . . 4 ⊢ ([y / x] ¬ φ ↔ ¬ [y / x]φ) | |
| 4 | 2, 3 | bitr4i 243 | . . 3 ⊢ (¬ y ∈ {x ∣ φ} ↔ [y / x] ¬ φ) |
| 5 | vex 2863 | . . . 4 ⊢ y ∈ V | |
| 6 | 5 | elcompl 3226 | . . 3 ⊢ (y ∈ ∼ {x ∣ φ} ↔ ¬ y ∈ {x ∣ φ}) |
| 7 | df-clab 2340 | . . 3 ⊢ (y ∈ {x ∣ ¬ φ} ↔ [y / x] ¬ φ) | |
| 8 | 4, 6, 7 | 3bitr4i 268 | . 2 ⊢ (y ∈ ∼ {x ∣ φ} ↔ y ∈ {x ∣ ¬ φ}) |
| 9 | 8 | eqriv 2350 | 1 ⊢ ∼ {x ∣ φ} = {x ∣ ¬ φ} |
| Colors of variables: wff setvar class |
| Syntax hints: ¬ wn 3 = wceq 1642 [wsb 1648 ∈ wcel 1710 {cab 2339 ∼ ccompl 3206 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-6 1729 ax-7 1734 ax-11 1746 ax-12 1925 ax-ext 2334 |
| This theorem depends on definitions: df-bi 177 df-or 359 df-an 360 df-nan 1288 df-tru 1319 df-ex 1542 df-nf 1545 df-sb 1649 df-clab 2340 df-cleq 2346 df-clel 2349 df-nfc 2479 df-v 2862 df-nin 3212 df-compl 3213 |
| This theorem is referenced by: nulnnn 4557 addccan2nclem2 6265 |
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