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Theorem cdeqeq 2950
Description: Distribute conditional equality over equality. (Contributed by Mario Carneiro, 11-Aug-2016.)
Hypotheses
Ref Expression
cdeqeq.1 CondEq(𝑥 = 𝑦𝐴 = 𝐵)
cdeqeq.2 CondEq(𝑥 = 𝑦𝐶 = 𝐷)
Assertion
Ref Expression
cdeqeq CondEq(𝑥 = 𝑦 → (𝐴 = 𝐶𝐵 = 𝐷))

Proof of Theorem cdeqeq
StepHypRef Expression
1 cdeqeq.1 . . . 4 CondEq(𝑥 = 𝑦𝐴 = 𝐵)
21cdeqri 2941 . . 3 (𝑥 = 𝑦𝐴 = 𝐵)
3 cdeqeq.2 . . . 4 CondEq(𝑥 = 𝑦𝐶 = 𝐷)
43cdeqri 2941 . . 3 (𝑥 = 𝑦𝐶 = 𝐷)
52, 4eqeq12d 2185 . 2 (𝑥 = 𝑦 → (𝐴 = 𝐶𝐵 = 𝐷))
65cdeqi 2940 1 CondEq(𝑥 = 𝑦 → (𝐴 = 𝐶𝐵 = 𝐷))
Colors of variables: wff set class
Syntax hints:  wb 104   = wceq 1348  CondEqwcdeq 2938
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1440  ax-gen 1442  ax-4 1503  ax-17 1519  ax-ext 2152
This theorem depends on definitions:  df-bi 116  df-cleq 2163  df-cdeq 2939
This theorem is referenced by: (None)
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