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Theorem ralnex 2538
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 2533 . 2 (∀𝑥𝐴 ¬ 𝜑 ↔ ∀𝑥(𝑥𝐴 → ¬ 𝜑))
2 alinexa 1656 . . 3 (∀𝑥(𝑥𝐴 → ¬ 𝜑) ↔ ¬ ∃𝑥(𝑥𝐴𝜑))
3 df-rex 2534 . . 3 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
42, 3xchbinxr 694 . 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 1400  wex 1545  wcel 2209  wral 2528  wrex 2529
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 623  ax-in2 624  ax-5 1500  ax-gen 1502  ax-ie2 1547
This theorem depends on definitions:  df-bi 117  df-tru 1405  df-fal 1408  df-ral 2533  df-rex 2534
This theorem is referenced by:  nnral  2540  rexalim  2543  ralinexa  2577  nrex  2642  nrexdv  2643  ralnex2  2690  r19.30dc  2698  uni0b  3955  iindif2m  4075  f0rn0  5582  supmoti  7323  fodjuomnilemdc  7474  ismkvnex  7485  nninfwlpoimlemginf  7506  suprnubex  9273  icc0r  10307  ioo0  10672  ico0  10674  ioc0  10675  prmind2  12876  sqrt2irr  12918  umgrnloop0  16272  vtxd0nedgbfi  16454  1hevtxdg0fi  16462  nconstwlpolem  17020
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