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Theorem ralnex 2518
Description: Relationship between restricted universal and existential quantifiers. (Contributed by NM, 21-Jan-1997.)
Assertion
Ref Expression
ralnex (∀𝑥𝐴 ¬ 𝜑 ↔ ¬ ∃𝑥𝐴 𝜑)

Proof of Theorem ralnex
StepHypRef Expression
1 df-ral 2513 . 2 (∀𝑥𝐴 ¬ 𝜑 ↔ ∀𝑥(𝑥𝐴 → ¬ 𝜑))
2 alinexa 1649 . . 3 (∀𝑥(𝑥𝐴 → ¬ 𝜑) ↔ ¬ ∃𝑥(𝑥𝐴𝜑))
3 df-rex 2514 . . 3 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
42, 3xchbinxr 687 . 2 (∀𝑥(𝑥𝐴 → ¬ 𝜑) ↔ ¬ ∃𝑥𝐴 𝜑)
51, 4bitri 184 1 (∀𝑥𝐴 ¬ 𝜑 ↔ ¬ ∃𝑥𝐴 𝜑)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 104  wb 105  wal 1393  wex 1538  wcel 2200  wral 2508  wrex 2509
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-in1 617  ax-in2 618  ax-5 1493  ax-gen 1495  ax-ie2 1540
This theorem depends on definitions:  df-bi 117  df-tru 1398  df-fal 1401  df-ral 2513  df-rex 2514
This theorem is referenced by:  nnral  2520  rexalim  2523  ralinexa  2557  nrex  2622  nrexdv  2623  ralnex2  2670  r19.30dc  2678  uni0b  3913  iindif2m  4033  f0rn0  5522  supmoti  7171  fodjuomnilemdc  7322  ismkvnex  7333  nninfwlpoimlemginf  7354  suprnubex  9111  icc0r  10134  ioo0  10491  ico0  10493  ioc0  10494  prmind2  12657  sqrt2irr  12699  umgrnloop0  15932  nconstwlpolem  16493
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