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Theorem r19.42v 2654
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 2653 . 2 (∃𝑥𝐴 (𝜓𝜑) ↔ (∃𝑥𝐴 𝜓𝜑))
2 ancom 266 . . 3 ((𝜑𝜓) ↔ (𝜓𝜑))
32rexbii 2504 . 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 2476
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 1461  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-4 1524  ax-17 1540  ax-ial 1548
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1475  df-rex 2481
This theorem is referenced by:  ceqsrexbv  2895  ceqsrex2v  2896  2reuswapdc  2968  iunrab  3965  iunin2  3981  iundif2ss  3983  iunopab  4317  elxp2  4682  cnvuni  4853  elunirn  5816  f1oiso  5876  oprabrexex2  6196  genpdflem  7591  1idprl  7674  1idpru  7675  ltexprlemm  7684  rexuz2  9672  4fvwrd4  10232  divalgb  12107
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