Metamath Proof Explorer

Theorem pm3.45

Description: Theorem *3.45 (Fact) of WhiteheadRussell p. 113. (Contributed by NM, 3-Jan-2005)

Ref Expression
Assertion pm3.45 
|- ( ( ph -> ps ) -> ( ( ph /\ ch ) -> ( ps /\ ch ) ) )

Proof

Step Hyp Ref Expression
1 id 
 |-  ( ( ph -> ps ) -> ( ph -> ps ) )
2 1 anim1d 
 |-  ( ( ph -> ps ) -> ( ( ph /\ ch ) -> ( ps /\ ch ) ) )