Metamath Proof Explorer


Theorem sylan9bbr

Description: Nested syllogism inference conjoining dissimilar antecedents. (Contributed by NM, 4-Mar-1995)

Ref Expression
Hypotheses sylan9bbr.1
|- ( ph -> ( ps <-> ch ) )
sylan9bbr.2
|- ( th -> ( ch <-> ta ) )
Assertion sylan9bbr
|- ( ( th /\ ph ) -> ( ps <-> ta ) )

Proof

Step Hyp Ref Expression
1 sylan9bbr.1
 |-  ( ph -> ( ps <-> ch ) )
2 sylan9bbr.2
 |-  ( th -> ( ch <-> ta ) )
3 1 2 sylan9bb
 |-  ( ( ph /\ th ) -> ( ps <-> ta ) )
4 3 ancoms
 |-  ( ( th /\ ph ) -> ( ps <-> ta ) )