Theorem pm5.74ri 180

Description: Distribution of implication over biconditional (reverse inference form). (Contributed by NM, 1-Aug-1994.)

Hypothesis

Ref	Expression
pm5.74ri.1	⊢ ((𝜑 → 𝜓) ↔ (𝜑 → 𝜒))

Assertion

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

Proof of Theorem pm5.74ri

Step	Hyp	Ref	Expression
1		pm5.74ri.1	. 2 ⊢ ((𝜑 → 𝜓) ↔ (𝜑 → 𝜒))
2		pm5.74 178	. 2 ⊢ ((𝜑 → (𝜓 ↔ 𝜒)) ↔ ((𝜑 → 𝜓) ↔ (𝜑 → 𝜒)))
3	1, 2	mpbir 145	1 ⊢ (𝜑 → (𝜓 ↔ 𝜒))

Syntax hints:   → wi 4   ↔ wb 104

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107

This theorem depends on definitions:  df-bi 116

This theorem is referenced by:  bitrd  187  bibi2d  231  tbt  246  cbval2  1909  sbco2d  1954  sbco2vd  1955  isprm2  12049