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| Mirrors > Home > ILE Home > Th. List > rexbidv2 | GIF version | ||
| Description: Formula-building rule for restricted existential quantifier (deduction form). (Contributed by NM, 22-May-1999.) |
| Ref | Expression |
|---|---|
| rexbidv2.1 | ⊢ (𝜑 → ((𝑥 ∈ 𝐴 ∧ 𝜓) ↔ (𝑥 ∈ 𝐵 ∧ 𝜒))) |
| Ref | Expression |
|---|---|
| rexbidv2 | ⊢ (𝜑 → (∃𝑥 ∈ 𝐴 𝜓 ↔ ∃𝑥 ∈ 𝐵 𝜒)) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rexbidv2.1 | . . 3 ⊢ (𝜑 → ((𝑥 ∈ 𝐴 ∧ 𝜓) ↔ (𝑥 ∈ 𝐵 ∧ 𝜒))) | |
| 2 | 1 | exbidv 1849 | . 2 ⊢ (𝜑 → (∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜓) ↔ ∃𝑥(𝑥 ∈ 𝐵 ∧ 𝜒))) |
| 3 | df-rex 2491 | . 2 ⊢ (∃𝑥 ∈ 𝐴 𝜓 ↔ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜓)) | |
| 4 | df-rex 2491 | . 2 ⊢ (∃𝑥 ∈ 𝐵 𝜒 ↔ ∃𝑥(𝑥 ∈ 𝐵 ∧ 𝜒)) | |
| 5 | 2, 3, 4 | 3bitr4g 223 | 1 ⊢ (𝜑 → (∃𝑥 ∈ 𝐴 𝜓 ↔ ∃𝑥 ∈ 𝐵 𝜒)) |
| Colors of variables: wff set class |
| Syntax hints: → wi 4 ∧ wa 104 ↔ wb 105 ∃wex 1516 ∈ wcel 2177 ∃wrex 2486 |
| 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-5 1471 ax-gen 1473 ax-ie1 1517 ax-ie2 1518 ax-4 1534 ax-17 1550 ax-ial 1558 |
| This theorem depends on definitions: df-bi 117 df-rex 2491 |
| This theorem is referenced by: rexss 3262 rexsupp 5714 isoini 5897 elfi2 7086 ltexpi 7463 rexuz 9714 4sqexercise2 12772 4sqlemsdc 12773 sscoll2 16038 |
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