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Theorem cbvexvw 1892
 Description: Change bound variable. See cbvexv 1890 for a version with fewer disjoint variable conditions. (Contributed by NM, 19-Apr-2017.)
Hypothesis
Ref Expression
cbvalvw.1 (𝑥 = 𝑦 → (𝜑𝜓))
Assertion
Ref Expression
cbvexvw (∃𝑥𝜑 ↔ ∃𝑦𝜓)
Distinct variable groups:   𝑥,𝑦   𝜓,𝑥   𝜑,𝑦
Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦)

Proof of Theorem cbvexvw
StepHypRef Expression
1 cbvalvw.1 . 2 (𝑥 = 𝑦 → (𝜑𝜓))
21cbvexv 1890 1 (∃𝑥𝜑 ↔ ∃𝑦𝜓)
 Colors of variables: wff set class Syntax hints:   → wi 4   ↔ wb 104  ∃wex 1468 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 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514 This theorem depends on definitions:  df-bi 116 This theorem is referenced by:  prodmodc  11359
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