Theorem truxorfal 1398

Description: A \/_ identity. (Contributed by David A. Wheeler, 2-Mar-2018.)

Assertion

Ref	Expression
truxorfal	|- ( ( T. \/_ F. ) <-> T. )

Proof of Theorem truxorfal

Step	Hyp	Ref	Expression
1		df-xor 1354	. 2 |- ( ( T. \/_ F. ) <-> ( ( T. \/ F. ) /\ -. ( T. /\ F. ) ) )
2		truorfal 1384	. . 3 |- ( ( T. \/ F. ) <-> T. )
3		notfal 1392	. . . 4 |- ( -. F. <-> T. )
4		truan 1348	. . . 4 |- ( ( T. /\ F. ) <-> F. )
5	3, 4	xchnxbir 670	. . 3 |- ( -. ( T. /\ F. ) <-> T. )
6	2, 5	anbi12i 455	. 2 |- ( ( ( T. \/ F. ) /\ -. ( T. /\ F. ) ) <-> ( T. /\ T. ) )
7		anidm 393	. 2 |- ( ( T. /\ T. ) <-> T. )
8	1, 6, 7	3bitri 205	1 |- ( ( T. \/_ F. ) <-> T. )

Syntax hints:   -. wn 3   /\ wa 103   <-> wb 104   \/ wo 697   T. wtru 1332   F. wfal 1336   \/_ wxo 1353

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 603  ax-in2 604  ax-io 698

This theorem depends on definitions:  df-bi 116  df-tru 1334  df-fal 1337  df-xor 1354

This theorem is referenced by: (None)