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Theorem reximi2 2415
 Description: Inference quantifying both antecedent and consequent, based on Theorem 19.22 of [Margaris] p. 90. (Contributed by NM, 8-Nov-2004.)
Hypothesis
Ref Expression
reximi2.1 ((𝑥𝐴𝜑) → (𝑥𝐵𝜓))
Assertion
Ref Expression
reximi2 (∃𝑥𝐴 𝜑 → ∃𝑥𝐵 𝜓)

Proof of Theorem reximi2
StepHypRef Expression
1 reximi2.1 . . 3 ((𝑥𝐴𝜑) → (𝑥𝐵𝜓))
21eximi 1491 . 2 (∃𝑥(𝑥𝐴𝜑) → ∃𝑥(𝑥𝐵𝜓))
3 df-rex 2312 . 2 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
4 df-rex 2312 . 2 (∃𝑥𝐵 𝜓 ↔ ∃𝑥(𝑥𝐵𝜓))
52, 3, 43imtr4i 190 1 (∃𝑥𝐴 𝜑 → ∃𝑥𝐵 𝜓)
 Colors of variables: wff set class Syntax hints:   → wi 4   ∧ wa 97  ∃wex 1381   ∈ wcel 1393  ∃wrex 2307 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-5 1336  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-4 1400  ax-ial 1427 This theorem depends on definitions:  df-bi 110  df-rex 2312 This theorem is referenced by:  btwnz  8357
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