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Theorem necon2i 2563
Description: Contrapositive inference for inequality. (Contributed by NM, 18-Mar-2007.)
Hypothesis
Ref Expression
necon2i.1
Assertion
Ref Expression
necon2i

Proof of Theorem necon2i
StepHypRef Expression
1 necon2i.1 . . 3
21neneqd 2532 . 2
32necon2ai 2561 1
Colors of variables: wff setvar class
Syntax hints:   wi 4   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:  map0  6025
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