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Theorem necon2bbii 2572
Description: Contrapositive inference for inequality. (Contributed by NM, 13-Apr-2007.)
Hypothesis
Ref Expression
necon2bbii.1
Assertion
Ref Expression
necon2bbii

Proof of Theorem necon2bbii
StepHypRef Expression
1 necon2bbii.1 . . . 4
21bicomi 193 . . 3
32necon1bbii 2568 . 2
43bicomi 193 1
Colors of variables: wff setvar class
Syntax hints:   wn 3   wb 176   wceq 1642   wne 2516
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 177  df-ne 2518
This theorem is referenced by:  dfaddc2  4381  xpeq0  5046
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