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Mirrors > Home > ILE Home > Th. List > ceqsexv | GIF version |
Description: Elimination of an existential quantifier, using implicit substitution. (Contributed by NM, 2-Mar-1995.) |
Ref | Expression |
---|---|
ceqsexv.1 | ⊢ 𝐴 ∈ V |
ceqsexv.2 | ⊢ (𝑥 = 𝐴 → (𝜑 ↔ 𝜓)) |
Ref | Expression |
---|---|
ceqsexv | ⊢ (∃𝑥(𝑥 = 𝐴 ∧ 𝜑) ↔ 𝜓) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfv 1473 | . 2 ⊢ Ⅎ𝑥𝜓 | |
2 | ceqsexv.1 | . 2 ⊢ 𝐴 ∈ V | |
3 | ceqsexv.2 | . 2 ⊢ (𝑥 = 𝐴 → (𝜑 ↔ 𝜓)) | |
4 | 1, 2, 3 | ceqsex 2671 | 1 ⊢ (∃𝑥(𝑥 = 𝐴 ∧ 𝜑) ↔ 𝜓) |
Colors of variables: wff set class |
Syntax hints: → wi 4 ∧ wa 103 ↔ wb 104 = wceq 1296 ∃wex 1433 ∈ wcel 1445 Vcvv 2633 |
This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-5 1388 ax-gen 1390 ax-ie1 1434 ax-ie2 1435 ax-8 1447 ax-4 1452 ax-17 1471 ax-i9 1475 ax-ial 1479 ax-ext 2077 |
This theorem depends on definitions: df-bi 116 df-nf 1402 df-sb 1700 df-clab 2082 df-cleq 2088 df-clel 2091 df-v 2635 |
This theorem is referenced by: ceqsex3v 2675 gencbvex 2679 sbhypf 2682 euxfr2dc 2814 inuni 4012 eqvinop 4094 onm 4252 uniuni 4301 opeliunxp 4522 elvvv 4530 rexiunxp 4609 imai 4821 coi1 4980 abrexco 5576 opabex3d 5930 opabex3 5931 mapsnen 6608 xpsnen 6617 xpcomco 6622 xpassen 6626 |
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