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Theorem pm2.21dd 99
Description: A contradiction implies anything. Deduction from pm2.21 100. (Contributed by Mario Carneiro, 9-Feb-2017.)
Hypotheses
Ref Expression
pm2.21dd.1
pm2.21dd.2
Assertion
Ref Expression
pm2.21dd

Proof of Theorem pm2.21dd
StepHypRef Expression
1 pm2.21dd.1 . 2
2 pm2.21dd.2 . . 3
32pm2.21d 98 . 2
41, 3mpd 14 1
Colors of variables: wff setvar class
Syntax hints:   wn 3   wi 4
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem is referenced by:  pm2.21fal  1335  pm2.21ddne  2590
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