Metamath Proof Explorer

Theorem 3mix3

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

Ref Expression
Assertion 3mix3 
|- ( ph -> ( ps \/ ch \/ ph ) )

Proof

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