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Theorem neeq12d 2305
Description: Deduction for inequality. (Contributed by NM, 24-Jul-2012.)
Hypotheses
Ref Expression
neeq1d.1  |-  ( ph  ->  A  =  B )
neeq12d.2  |-  ( ph  ->  C  =  D )
Assertion
Ref Expression
neeq12d  |-  ( ph  ->  ( A  =/=  C  <->  B  =/=  D ) )

Proof of Theorem neeq12d
StepHypRef Expression
1 neeq1d.1 . . 3  |-  ( ph  ->  A  =  B )
21neeq1d 2303 . 2  |-  ( ph  ->  ( A  =/=  C  <->  B  =/=  C ) )
3 neeq12d.2 . . 3  |-  ( ph  ->  C  =  D )
43neeq2d 2304 . 2  |-  ( ph  ->  ( B  =/=  C  <->  B  =/=  D ) )
52, 4bitrd 187 1  |-  ( ph  ->  ( A  =/=  C  <->  B  =/=  D ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 104    = wceq 1316    =/= wne 2285
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 588  ax-in2 589  ax-5 1408  ax-gen 1410  ax-4 1472  ax-17 1491  ax-ext 2099
This theorem depends on definitions:  df-bi 116  df-cleq 2110  df-ne 2286
This theorem is referenced by:  3netr3d  2317  3netr4d  2318  ennnfonelemim  11864  ctinfom  11868
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