Metamath Proof Explorer


Theorem ancomsd

Description: Deduction commuting conjunction in antecedent. (Contributed by NM, 12-Dec-2004)

Ref Expression
Hypothesis ancomsd.1 φψχθ
Assertion ancomsd φχψθ

Proof

Step Hyp Ref Expression
1 ancomsd.1 φψχθ
2 1 expcomd φχψθ
3 2 impd φχψθ