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| Mirrors > Home > NFE Home > Th. List > elab4g | GIF version | ||
| Description: Membership in a class abstraction, using implicit substitution. (Contributed by NM, 17-Oct-2012.) |
| Ref | Expression |
|---|---|
| elab4g.1 | ⊢ (x = A → (φ ↔ ψ)) |
| elab4g.2 | ⊢ B = {x ∣ φ} |
| Ref | Expression |
|---|---|
| elab4g | ⊢ (A ∈ B ↔ (A ∈ V ∧ ψ)) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elex 2868 | . 2 ⊢ (A ∈ B → A ∈ V) | |
| 2 | elab4g.1 | . . 3 ⊢ (x = A → (φ ↔ ψ)) | |
| 3 | elab4g.2 | . . 3 ⊢ B = {x ∣ φ} | |
| 4 | 2, 3 | elab2g 2988 | . 2 ⊢ (A ∈ V → (A ∈ B ↔ ψ)) |
| 5 | 1, 4 | biadan2 623 | 1 ⊢ (A ∈ B ↔ (A ∈ V ∧ ψ)) |
| Colors of variables: wff setvar class |
| Syntax hints: → wi 4 ↔ wb 176 ∧ wa 358 = wceq 1642 ∈ wcel 1710 {cab 2339 Vcvv 2860 |
| 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-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 |
| This theorem is referenced by: (None) |
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