Theorem pm5.74da 417

Description: Distribution of implication over biconditional (deduction rule). (Contributed by NM, 4-May-2007.)

Hypothesis

Ref	Expression
pm5.74da.1	⊢ ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃))

Assertion

Ref	Expression
pm5.74da	⊢ (𝜑 → ((𝜓 → 𝜒) ↔ (𝜓 → 𝜃)))

Proof of Theorem pm5.74da

Step	Hyp	Ref	Expression
1		pm5.74da.1	. . 3 ⊢ ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃))
2	1	ex 108	. 2 ⊢ (𝜑 → (𝜓 → (𝜒 ↔ 𝜃)))
3	2	pm5.74d 171	1 ⊢ (𝜑 → ((𝜓 → 𝜒) ↔ (𝜓 → 𝜃)))

Syntax hints:   → wi 4   ∧ wa 97   ↔ wb 98

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101

This theorem depends on definitions:  df-bi 110

This theorem is referenced by:  ralbida  2320  elrab3t  2697  dff13  5407