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Theorem ralnex 2485
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 2480 . 2 (∀𝑥𝐴 ¬ 𝜑 ↔ ∀𝑥(𝑥𝐴 → ¬ 𝜑))
2 alinexa 1617 . . 3 (∀𝑥(𝑥𝐴 → ¬ 𝜑) ↔ ¬ ∃𝑥(𝑥𝐴𝜑))
3 df-rex 2481 . . 3 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
42, 3xchbinxr 684 . 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 1362  wex 1506  wcel 2167  wral 2475  wrex 2476
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 615  ax-in2 616  ax-5 1461  ax-gen 1463  ax-ie2 1508
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-fal 1370  df-ral 2480  df-rex 2481
This theorem is referenced by:  nnral  2487  rexalim  2490  ralinexa  2524  nrex  2589  nrexdv  2590  ralnex2  2636  r19.30dc  2644  uni0b  3865  iindif2m  3985  f0rn0  5453  supmoti  7060  fodjuomnilemdc  7211  ismkvnex  7222  nninfwlpoimlemginf  7243  suprnubex  8982  icc0r  10003  ioo0  10351  ico0  10353  ioc0  10354  prmind2  12298  sqrt2irr  12340  nconstwlpolem  15719
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