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Theorem cdeqal 2776
 Description: Distribute conditional equality over quantification. (Contributed by Mario Carneiro, 11-Aug-2016.)
Hypothesis
Ref Expression
cdeqnot.1 CondEq(𝑥 = 𝑦 → (𝜑𝜓))
Assertion
Ref Expression
cdeqal CondEq(𝑥 = 𝑦 → (∀𝑧𝜑 ↔ ∀𝑧𝜓))
Distinct variable groups:   𝑥,𝑧   𝑦,𝑧
Allowed substitution hints:   𝜑(𝑥,𝑦,𝑧)   𝜓(𝑥,𝑦,𝑧)

Proof of Theorem cdeqal
StepHypRef Expression
1 cdeqnot.1 . . . 4 CondEq(𝑥 = 𝑦 → (𝜑𝜓))
21cdeqri 2773 . . 3 (𝑥 = 𝑦 → (𝜑𝜓))
32albidv 1721 . 2 (𝑥 = 𝑦 → (∀𝑧𝜑 ↔ ∀𝑧𝜓))
43cdeqi 2772 1 CondEq(𝑥 = 𝑦 → (∀𝑧𝜑 ↔ ∀𝑧𝜓))
 Colors of variables: wff set class Syntax hints:   ↔ wb 102  ∀wal 1257  CondEqwcdeq 2770 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 103  ax-ia2 104  ax-ia3 105  ax-5 1352  ax-gen 1354  ax-17 1435 This theorem depends on definitions:  df-bi 114  df-cdeq 2771 This theorem is referenced by: (None)
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