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Theorem reximi2 2432
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 1507 . 2 (∃𝑥(𝑥𝐴𝜑) → ∃𝑥(𝑥𝐵𝜓))
3 df-rex 2329 . 2 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
4 df-rex 2329 . 2 (∃𝑥𝐵 𝜓 ↔ ∃𝑥(𝑥𝐵𝜓))
52, 3, 43imtr4i 194 1 (∃𝑥𝐴 𝜑 → ∃𝑥𝐵 𝜓)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 101  wex 1397  wcel 1409  wrex 2324
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 103  ax-ia2 104  ax-ia3 105  ax-5 1352  ax-gen 1354  ax-ie1 1398  ax-ie2 1399  ax-4 1416  ax-ial 1443
This theorem depends on definitions:  df-bi 114  df-rex 2329
This theorem is referenced by:  btwnz  8416  ioo0  9216
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