Metamath Proof Explorer


Theorem ancr

Description: Conjoin antecedent to right of consequent. (Contributed by NM, 15-Aug-1994)

Ref Expression
Assertion ancr ( ( 𝜑𝜓 ) → ( 𝜑 → ( 𝜓𝜑 ) ) )

Proof

Step Hyp Ref Expression
1 pm3.21 ( 𝜑 → ( 𝜓 → ( 𝜓𝜑 ) ) )
2 1 a2i ( ( 𝜑𝜓 ) → ( 𝜑 → ( 𝜓𝜑 ) ) )