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Mirrors > Home > NFE Home > Th. List > elab | GIF version |
Description: Membership in a class abstraction, using implicit substitution. Compare Theorem 6.13 of [Quine] p. 44. (Contributed by NM, 1-Aug-1994.) |
Ref | Expression |
---|---|
elab.1 | ⊢ A ∈ V |
elab.2 | ⊢ (x = A → (φ ↔ ψ)) |
Ref | Expression |
---|---|
elab | ⊢ (A ∈ {x ∣ φ} ↔ ψ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfv 1619 | . 2 ⊢ Ⅎxψ | |
2 | elab.1 | . 2 ⊢ A ∈ V | |
3 | elab.2 | . 2 ⊢ (x = A → (φ ↔ ψ)) | |
4 | 1, 2, 3 | elabf 2985 | 1 ⊢ (A ∈ {x ∣ φ} ↔ ψ) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ↔ wb 176 = 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: ralab 2998 rexab 3000 intab 3957 dfiin2g 4001 pwadjoin 4120 dfnnc2 4396 findsd 4411 nnadjoinlem1 4520 tfinnn 4535 vfinncvntsp 4550 vfinspss 4552 vfinspclt 4553 proj1op 4601 proj2op 4602 funcnvuni 5162 fun11iun 5306 tz6.12-2 5347 fnasrn 5418 abrexco 5464 clos1is 5882 mapval2 6019 mucex 6134 ceex 6175 spacis 6289 |
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