Theorem 3mix2 1074

Description: Introduction in triple disjunction. (Contributed by NM, 4-Apr-1995.)

Assertion

Ref	Expression
3mix2	|- ( ph -> ( ps \/ ph \/ ch ) )

Proof of Theorem 3mix2

Step	Hyp	Ref	Expression
1		3mix1 1073	. 2 |- ( ph -> ( ph \/ ch \/ ps ) )
2		3orrot 891	. 2 |- ( ( ps \/ ph \/ ch ) <-> ( ph \/ ch \/ ps ) )
3	1, 2	sylibr 137	1 |- ( ph -> ( ps \/ ph \/ ch ) )

Syntax hints:   -> wi 4   \/ w3o 884

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-io 630

This theorem depends on definitions:  df-bi 110  df-3or 886

This theorem is referenced by:  3mix2i  1077  3mix2d  1080  3jaob  1197  funtpg  4950  elnn0z  8258  nn01to3  8552