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| Mirrors > Home > ILE Home > Th. List > r19.21t | GIF version | ||
| Description: Theorem 19.21 of [Margaris] p. 90 with restricted quantifiers (closed theorem version). (Contributed by NM, 1-Mar-2008.) | 
| Ref | Expression | 
|---|---|
| r19.21t | ⊢ (Ⅎ𝑥𝜑 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ (𝜑 → ∀𝑥 ∈ 𝐴 𝜓))) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | bi2.04 248 | . . . 4 ⊢ ((𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) ↔ (𝜑 → (𝑥 ∈ 𝐴 → 𝜓))) | |
| 2 | 1 | albii 1484 | . . 3 ⊢ (∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) ↔ ∀𝑥(𝜑 → (𝑥 ∈ 𝐴 → 𝜓))) | 
| 3 | 19.21t 1596 | . . 3 ⊢ (Ⅎ𝑥𝜑 → (∀𝑥(𝜑 → (𝑥 ∈ 𝐴 → 𝜓)) ↔ (𝜑 → ∀𝑥(𝑥 ∈ 𝐴 → 𝜓)))) | |
| 4 | 2, 3 | bitrid 192 | . 2 ⊢ (Ⅎ𝑥𝜑 → (∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓)) ↔ (𝜑 → ∀𝑥(𝑥 ∈ 𝐴 → 𝜓)))) | 
| 5 | df-ral 2480 | . 2 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓))) | |
| 6 | df-ral 2480 | . . 3 ⊢ (∀𝑥 ∈ 𝐴 𝜓 ↔ ∀𝑥(𝑥 ∈ 𝐴 → 𝜓)) | |
| 7 | 6 | imbi2i 226 | . 2 ⊢ ((𝜑 → ∀𝑥 ∈ 𝐴 𝜓) ↔ (𝜑 → ∀𝑥(𝑥 ∈ 𝐴 → 𝜓))) | 
| 8 | 4, 5, 7 | 3bitr4g 223 | 1 ⊢ (Ⅎ𝑥𝜑 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ (𝜑 → ∀𝑥 ∈ 𝐴 𝜓))) | 
| Colors of variables: wff set class | 
| Syntax hints: → wi 4 ↔ wb 105 ∀wal 1362 Ⅎwnf 1474 ∈ wcel 2167 ∀wral 2475 | 
| 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 1461 ax-gen 1463 ax-4 1524 ax-ial 1548 ax-i5r 1549 | 
| This theorem depends on definitions: df-bi 117 df-nf 1475 df-ral 2480 | 
| This theorem is referenced by: r19.21 2573 | 
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