Metamath Proof Explorer


Theorem pm5.32da

Description: Distribution of implication over biconditional (deduction form). (Contributed by NM, 9-Dec-2006)

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

Proof

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