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Mirrors > Home > ILE Home > Th. List > rexim | GIF version |
Description: Theorem 19.22 of [Margaris] p. 90. (Restricted quantifier version.) (Contributed by NM, 22-Nov-1994.) (Proof shortened by Andrew Salmon, 30-May-2011.) |
Ref | Expression |
---|---|
rexim | ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → (∃𝑥 ∈ 𝐴 𝜑 → ∃𝑥 ∈ 𝐴 𝜓)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-ral 2353 | . . . 4 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓))) | |
2 | simpl 107 | . . . . . . 7 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝑥 ∈ 𝐴) | |
3 | 2 | a1i 9 | . . . . . 6 ⊢ ((𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) → ((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝑥 ∈ 𝐴)) |
4 | pm3.31 258 | . . . . . 6 ⊢ ((𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) → ((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓)) | |
5 | 3, 4 | jcad 301 | . . . . 5 ⊢ ((𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) → ((𝑥 ∈ 𝐴 ∧ 𝜑) → (𝑥 ∈ 𝐴 ∧ 𝜓))) |
6 | 5 | alimi 1384 | . . . 4 ⊢ (∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) → ∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → (𝑥 ∈ 𝐴 ∧ 𝜓))) |
7 | 1, 6 | sylbi 119 | . . 3 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → ∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → (𝑥 ∈ 𝐴 ∧ 𝜓))) |
8 | exim 1530 | . . 3 ⊢ (∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → (𝑥 ∈ 𝐴 ∧ 𝜓)) → (∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) → ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜓))) | |
9 | 7, 8 | syl 14 | . 2 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → (∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) → ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜓))) |
10 | df-rex 2354 | . 2 ⊢ (∃𝑥 ∈ 𝐴 𝜑 ↔ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)) | |
11 | df-rex 2354 | . 2 ⊢ (∃𝑥 ∈ 𝐴 𝜓 ↔ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜓)) | |
12 | 9, 10, 11 | 3imtr4g 203 | 1 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) → (∃𝑥 ∈ 𝐴 𝜑 → ∃𝑥 ∈ 𝐴 𝜓)) |
Colors of variables: wff set class |
Syntax hints: → wi 4 ∧ wa 102 ∀wal 1282 ∃wex 1421 ∈ wcel 1433 ∀wral 2348 ∃wrex 2349 |
This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 104 ax-ia2 105 ax-ia3 106 ax-5 1376 ax-gen 1378 ax-ie1 1422 ax-ie2 1423 ax-4 1440 ax-ial 1467 |
This theorem depends on definitions: df-bi 115 df-ral 2353 df-rex 2354 |
This theorem is referenced by: reximia 2456 reximdai 2459 r19.29 2494 reupick2 3250 ss2iun 3693 chfnrn 5299 |
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