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Theorem ralnex 2521
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 2516 . 2 (∀𝑥𝐴 ¬ 𝜑 ↔ ∀𝑥(𝑥𝐴 → ¬ 𝜑))
2 alinexa 1652 . . 3 (∀𝑥(𝑥𝐴 → ¬ 𝜑) ↔ ¬ ∃𝑥(𝑥𝐴𝜑))
3 df-rex 2517 . . 3 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
42, 3xchbinxr 690 . 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 1396  wex 1541  wcel 2202  wral 2511  wrex 2512
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 619  ax-in2 620  ax-5 1496  ax-gen 1498  ax-ie2 1543
This theorem depends on definitions:  df-bi 117  df-tru 1401  df-fal 1404  df-ral 2516  df-rex 2517
This theorem is referenced by:  nnral  2523  rexalim  2526  ralinexa  2560  nrex  2625  nrexdv  2626  ralnex2  2673  r19.30dc  2681  uni0b  3923  iindif2m  4043  f0rn0  5540  supmoti  7235  fodjuomnilemdc  7386  ismkvnex  7397  nninfwlpoimlemginf  7418  suprnubex  9175  icc0r  10205  ioo0  10565  ico0  10567  ioc0  10568  prmind2  12755  sqrt2irr  12797  umgrnloop0  16041  vtxd0nedgbfi  16223  1hevtxdg0fi  16231  nconstwlpolem  16781
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