Theorem 2false 350

Description: Two falsehoods are equivalent. (Contributed by NM, 4-Apr-2005.) (Proof shortened by Wolf Lammen, 19-May-2013.)

Hypotheses

Ref	Expression
2false.1
2false.2

Assertion

Ref	Expression
2false

Proof of Theorem 2false

Step	Hyp	Ref	Expression
1		2false.1	. . 3
2		2false.2	. . 3
3	1, 2	2th 239	. 2
4	3	con4bii 297	1

Syntax hints:  -.wn 3  <->wb 184

This theorem is referenced by:  bianfi  916  bifal  1383  iun0  4343  0iun  4344  sbcbr  4462  0xp  5034  cnv0  5359  co02  5470  0er  7270  00lss  17199  00ply1bas  17875  signswch  27418  dandysum2p2e4  30866  pexmidlem8N  34472

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 185