Metamath Proof Explorer


Theorem simp1d

Description: Deduce a conjunct from a triple conjunction. (Contributed by NM, 4-Sep-2005)

Ref Expression
Hypothesis 3simp1d.1 φ ψ χ θ
Assertion simp1d φ ψ

Proof

Step Hyp Ref Expression
1 3simp1d.1 φ ψ χ θ
2 simp1 ψ χ θ ψ
3 1 2 syl φ ψ