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Theorem r19.42v 2691
Description: Restricted version of Theorem 19.42 of [Margaris] p. 90. (Contributed by NM, 27-May-1998.)
Assertion
Ref Expression
r19.42v (∃𝑥𝐴 (𝜑𝜓) ↔ (𝜑 ∧ ∃𝑥𝐴 𝜓))
Distinct variable group:   𝜑,𝑥
Allowed substitution hints:   𝜓(𝑥)   𝐴(𝑥)

Proof of Theorem r19.42v
StepHypRef Expression
1 r19.41v 2690 . 2 (∃𝑥𝐴 (𝜓𝜑) ↔ (∃𝑥𝐴 𝜓𝜑))
2 ancom 266 . . 3 ((𝜑𝜓) ↔ (𝜓𝜑))
32rexbii 2540 . 2 (∃𝑥𝐴 (𝜑𝜓) ↔ ∃𝑥𝐴 (𝜓𝜑))
4 ancom 266 . 2 ((𝜑 ∧ ∃𝑥𝐴 𝜓) ↔ (∃𝑥𝐴 𝜓𝜑))
51, 3, 43bitr4i 212 1 (∃𝑥𝐴 (𝜑𝜓) ↔ (𝜑 ∧ ∃𝑥𝐴 𝜓))
Colors of variables: wff set class
Syntax hints:  wa 104  wb 105  wrex 2512
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 1496  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-4 1559  ax-17 1575  ax-ial 1583
This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-rex 2517
This theorem is referenced by:  ceqsrexbv  2938  ceqsrex2v  2939  2reuswapdc  3011  iunrab  4023  iunin2  4039  iundif2ss  4041  iunopab  4382  elxp2  4749  cnvuni  4922  elunirn  5917  f1oiso  5977  oprabrexex2  6301  genpdflem  7770  1idprl  7853  1idpru  7854  ltexprlemm  7863  rexuz2  9859  4fvwrd4  10420  divalgb  12549
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