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Theorem truxorfal 1351
Description: A  \/_ identity. (Contributed by David A. Wheeler, 2-Mar-2018.)
Assertion
Ref Expression
truxorfal  |-  ( ( T.  \/_ F.  )  <-> T.  )

Proof of Theorem truxorfal
StepHypRef Expression
1 df-xor 1307 . 2  |-  ( ( T.  \/_ F.  )  <->  ( ( T.  \/ F.  )  /\  -.  ( T. 
/\ F.  ) )
)
2 truorfal 1337 . . 3  |-  ( ( T.  \/ F.  )  <-> T.  )
3 notfal 1345 . . . 4  |-  ( -. F.  <-> T.  )
4 truan 1301 . . . 4  |-  ( ( T.  /\ F.  )  <-> F.  )
53, 4xchnxbir 638 . . 3  |-  ( -.  ( T.  /\ F.  ) 
<-> T.  )
62, 5anbi12i 447 . 2  |-  ( ( ( T.  \/ F.  )  /\  -.  ( T. 
/\ F.  ) )  <->  ( T.  /\ T.  ) )
7 anidm 388 . 2  |-  ( ( T.  /\ T.  )  <-> T.  )
81, 6, 73bitri 204 1  |-  ( ( T.  \/_ F.  )  <-> T.  )
Colors of variables: wff set class
Syntax hints:   -. wn 3    /\ wa 102    <-> wb 103    \/ wo 661   T. wtru 1285   F. wfal 1289    \/_ wxo 1306
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-in1 576  ax-in2 577  ax-io 662
This theorem depends on definitions:  df-bi 115  df-tru 1287  df-fal 1290  df-xor 1307
This theorem is referenced by: (None)
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