Metamath Proof Explorer


Theorem syl3an2b

Description: A syllogism inference. (Contributed by NM, 22-Aug-1995)

Ref Expression
Hypotheses syl3an2b.1
|- ( ph <-> ch )
syl3an2b.2
|- ( ( ps /\ ch /\ th ) -> ta )
Assertion syl3an2b
|- ( ( ps /\ ph /\ th ) -> ta )

Proof

Step Hyp Ref Expression
1 syl3an2b.1
 |-  ( ph <-> ch )
2 syl3an2b.2
 |-  ( ( ps /\ ch /\ th ) -> ta )
3 1 biimpi
 |-  ( ph -> ch )
4 3 2 syl3an2
 |-  ( ( ps /\ ph /\ th ) -> ta )