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Theorem rexeqdv 2672
Description: Equality deduction for restricted existential quantifier. (Contributed by NM, 14-Jan-2007.)
Hypothesis
Ref Expression
raleq1d.1 (𝜑𝐴 = 𝐵)
Assertion
Ref Expression
rexeqdv (𝜑 → (∃𝑥𝐴 𝜓 ↔ ∃𝑥𝐵 𝜓))
Distinct variable groups:   𝑥,𝐴   𝑥,𝐵
Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑥)

Proof of Theorem rexeqdv
StepHypRef Expression
1 raleq1d.1 . 2 (𝜑𝐴 = 𝐵)
2 rexeq 2666 . 2 (𝐴 = 𝐵 → (∃𝑥𝐴 𝜓 ↔ ∃𝑥𝐵 𝜓))
31, 2syl 14 1 (𝜑 → (∃𝑥𝐴 𝜓 ↔ ∃𝑥𝐵 𝜓))
Colors of variables: wff set class
Syntax hints:  wi 4  wb 104   = wceq 1348  wrex 2449
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-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-ext 2152
This theorem depends on definitions:  df-bi 116  df-tru 1351  df-nf 1454  df-sb 1756  df-cleq 2163  df-clel 2166  df-nfc 2301  df-rex 2454
This theorem is referenced by:  rexeqbidv  2678  rexeqbidva  2680  fnunirn  5743  cbvexfo  5762  fival  6943  genipv  7458  exfzdc  10183  zproddc  11529  infssuzex  11891  nninfdcex  11895  ennnfonelemrnh  12358  cnpfval  12910
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