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| Mirrors > Home > ILE Home > Th. List > cdeqal | GIF version | ||
| Description: Distribute conditional equality over quantification. (Contributed by Mario Carneiro, 11-Aug-2016.) | 
| Ref | Expression | 
|---|---|
| cdeqnot.1 | ⊢ CondEq(𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) | 
| Ref | Expression | 
|---|---|
| cdeqal | ⊢ CondEq(𝑥 = 𝑦 → (∀𝑧𝜑 ↔ ∀𝑧𝜓)) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | cdeqnot.1 | . . . 4 ⊢ CondEq(𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) | |
| 2 | 1 | cdeqri 2975 | . . 3 ⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) | 
| 3 | 2 | albidv 1838 | . 2 ⊢ (𝑥 = 𝑦 → (∀𝑧𝜑 ↔ ∀𝑧𝜓)) | 
| 4 | 3 | cdeqi 2974 | 1 ⊢ CondEq(𝑥 = 𝑦 → (∀𝑧𝜑 ↔ ∀𝑧𝜓)) | 
| Colors of variables: wff set class | 
| Syntax hints: ↔ wb 105 ∀wal 1362 CondEqwcdeq 2972 | 
| 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-17 1540 | 
| This theorem depends on definitions: df-bi 117 df-cdeq 2973 | 
| This theorem is referenced by: (None) | 
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