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Theorem falxorfal 1310
Description: A identity. (Contributed by David A. Wheeler, 2-Mar-2018.)
Assertion
Ref Expression
falxorfal (( ⊥ ⊻ ⊥ ) ↔ ⊥ )

Proof of Theorem falxorfal
StepHypRef Expression
1 df-xor 1266 . 2 (( ⊥ ⊻ ⊥ ) ↔ (( ⊥ ⊥ ) ¬ ( ⊥ ⊥ )))
2 oridm 673 . . 3 (( ⊥ ⊥ ) ↔ ⊥ )
3 notfal 1302 . . . 4 (¬ ⊥ ↔ ⊤ )
4 anidm 376 . . . 4 (( ⊥ ⊥ ) ↔ ⊥ )
53, 4xchnxbir 605 . . 3 (¬ ( ⊥ ⊥ ) ↔ ⊤ )
62, 5anbi12i 433 . 2 ((( ⊥ ⊥ ) ¬ ( ⊥ ⊥ )) ↔ ( ⊥ ⊤ ))
7 falantru 1291 . 2 (( ⊥ ⊤ ) ↔ ⊥ )
81, 6, 73bitri 195 1 (( ⊥ ⊻ ⊥ ) ↔ ⊥ )
Colors of variables: wff set class
Syntax hints:  ¬ wn 3   wa 97  wb 98   wo 628  wtru 1243  wfal 1247  wxo 1265
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-in1 544  ax-in2 545  ax-io 629
This theorem depends on definitions:  df-bi 110  df-tru 1245  df-fal 1248  df-xor 1266
This theorem is referenced by: (None)
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