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Theorem ceqsexv 2587
 Description: Elimination of an existential quantifier, using implicit substitution. (Contributed by NM, 2-Mar-1995.)
Hypotheses
Ref Expression
ceqsexv.1 A V
ceqsexv.2 (x = A → (φψ))
Assertion
Ref Expression
ceqsexv (x(x = A φ) ↔ ψ)
Distinct variable groups:   x,A   ψ,x
Allowed substitution hint:   φ(x)

Proof of Theorem ceqsexv
StepHypRef Expression
1 nfv 1418 . 2 xψ
2 ceqsexv.1 . 2 A V
3 ceqsexv.2 . 2 (x = A → (φψ))
41, 2, 3ceqsex 2586 1 (x(x = A φ) ↔ ψ)
 Colors of variables: wff set class Syntax hints:   → wi 4   ∧ wa 97   ↔ wb 98   = wceq 1242  ∃wex 1378   ∈ wcel 1390  Vcvv 2551 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-5 1333  ax-gen 1335  ax-ie1 1379  ax-ie2 1380  ax-8 1392  ax-4 1397  ax-17 1416  ax-i9 1420  ax-ial 1424  ax-ext 2019 This theorem depends on definitions:  df-bi 110  df-nf 1347  df-sb 1643  df-clab 2024  df-cleq 2030  df-clel 2033  df-v 2553 This theorem is referenced by:  ceqsex3v  2590  gencbvex  2594  sbhypf  2597  euxfr2dc  2720  inuni  3900  eqvinop  3971  onm  4104  uniuni  4149  opeliunxp  4338  elvvv  4346  rexiunxp  4421  imai  4624  coi1  4779  abrexco  5341  opabex3d  5690  opabex3  5691  xpsnen  6231  xpcomco  6236  xpassen  6240
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