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  925  bifal  1408  iun0  4386  0iun  4387  sbcbr  4505  0xp  5085  cnv0  5414  co02  5526  0er  7365  00lss  17588  00ply1bas  18281  signswch  28518  dandysum2p2e4  32170  pexmidlem8N  35701

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