Metamath Proof Explorer


Theorem syl3an1br

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

Ref Expression
Hypotheses syl3an1br.1
|- ( ps <-> ph )
syl3an1br.2
|- ( ( ps /\ ch /\ th ) -> ta )
Assertion syl3an1br
|- ( ( ph /\ ch /\ th ) -> ta )

Proof

Step Hyp Ref Expression
1 syl3an1br.1
 |-  ( ps <-> ph )
2 syl3an1br.2
 |-  ( ( ps /\ ch /\ th ) -> ta )
3 1 biimpri
 |-  ( ph -> ps )
4 3 2 syl3an1
 |-  ( ( ph /\ ch /\ th ) -> ta )