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Theorem chvarfv 1700
Description: Implicit substitution of 𝑦 for 𝑥 into a theorem. Version of chvar 1757 with a disjoint variable condition. (Contributed by Raph Levien, 9-Jul-2003.) (Revised by BJ, 31-May-2019.)
Hypotheses
Ref Expression
chvarfv.nf 𝑥𝜓
chvarfv.1 (𝑥 = 𝑦 → (𝜑𝜓))
chvarfv.2 𝜑
Assertion
Ref Expression
chvarfv 𝜓
Distinct variable group:   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑥,𝑦)   𝜓(𝑥,𝑦)

Proof of Theorem chvarfv
StepHypRef Expression
1 chvarfv.nf . . 3 𝑥𝜓
2 chvarfv.1 . . . 4 (𝑥 = 𝑦 → (𝜑𝜓))
32biimpd 144 . . 3 (𝑥 = 𝑦 → (𝜑𝜓))
41, 3spimfv 1699 . 2 (∀𝑥𝜑𝜓)
5 chvarfv.2 . 2 𝜑
64, 5mpg 1451 1 𝜓
Colors of variables: wff set class
Syntax hints:  wi 4  wb 105  wnf 1460
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 1447  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-4 1510  ax-i9 1530  ax-ial 1534
This theorem depends on definitions:  df-bi 117  df-nf 1461
This theorem is referenced by:  fproddivapf  11638  fprodsplitf  11639
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