Metamath Proof Explorer


Theorem 3impdir

Description: Importation inference (undistribute conjunction). (Contributed by NM, 20-Aug-1995)

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

Proof

Step Hyp Ref Expression
1 3impdir.1 φ ψ χ ψ θ
2 1 anandirs φ χ ψ θ
3 2 3impa φ χ ψ θ