Metamath Proof Explorer

Theorem 3mix2

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

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

Proof

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