Metamath Proof Explorer


Theorem simp1

Description: Simplification of triple conjunction. (Contributed by NM, 21-Apr-1994) (Proof shortened by Wolf Lammen, 22-Jun-2022)

Ref Expression
Assertion simp1 φψχφ

Proof

Step Hyp Ref Expression
1 id φφ
2 1 3ad2ant1 φψχφ