Metamath Proof Explorer


Theorem pm5.32d

Description: Distribution of implication over biconditional (deduction form). (Contributed by NM, 29-Oct-1996)

Ref Expression
Hypothesis pm5.32d.1 ( 𝜑 → ( 𝜓 → ( 𝜒𝜃 ) ) )
Assertion pm5.32d ( 𝜑 → ( ( 𝜓𝜒 ) ↔ ( 𝜓𝜃 ) ) )

Proof

Step Hyp Ref Expression
1 pm5.32d.1 ( 𝜑 → ( 𝜓 → ( 𝜒𝜃 ) ) )
2 pm5.32 ( ( 𝜓 → ( 𝜒𝜃 ) ) ↔ ( ( 𝜓𝜒 ) ↔ ( 𝜓𝜃 ) ) )
3 1 2 sylib ( 𝜑 → ( ( 𝜓𝜒 ) ↔ ( 𝜓𝜃 ) ) )