Metamath Proof Explorer


Theorem anassrs

Description: Associative law for conjunction applied to antecedent (eliminates syllogism). (Contributed by NM, 15-Nov-2002)

Ref Expression
Hypothesis anassrs.1 φψχθ
Assertion anassrs φψχθ

Proof

Step Hyp Ref Expression
1 anassrs.1 φψχθ
2 1 exp32 φψχθ
3 2 imp31 φψχθ