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Theorem 2eximdv 1624
Description: Deduction from Theorem 19.22 of [Margaris] p. 90. (Contributed by NM, 3-Aug-1995.)
Hypothesis
Ref Expression
2alimdv.1 (φ → (ψχ))
Assertion
Ref Expression
2eximdv (φ → (xyψxyχ))
Distinct variable groups:   φ,x   φ,y
Allowed substitution hints:   ψ(x,y)   χ(x,y)

Proof of Theorem 2eximdv
StepHypRef Expression
1 2alimdv.1 . . 3 (φ → (ψχ))
21eximdv 1622 . 2 (φ → (yψyχ))
32eximdv 1622 1 (φ → (xyψxyχ))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wex 1541
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616
This theorem depends on definitions:  df-bi 177  df-ex 1542
This theorem is referenced by:  cgsex2g  2891  cgsex4g  2892  spc2egv  2941  spc3egv  2943
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