Metamath Proof Explorer


Theorem ibar

Description: Introduction of antecedent as conjunct. (Contributed by NM, 5-Dec-1995)

Ref Expression
Assertion ibar φ ψ φ ψ

Proof

Step Hyp Ref Expression
1 iba φ ψ ψ φ
2 1 biancomd φ ψ φ ψ