Theorem bi12imp3 42003

Description: Similar to 3imp 1109 except all but innermost implication are biconditionals. (Contributed by Alan Sare, 6-Nov-2017.)

Hypothesis

Ref	Expression
bi12imp3.1	⊢ (𝜑 ↔ (𝜓 ↔ (𝜒 → 𝜃)))

Assertion

Ref	Expression
bi12imp3	⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)

Proof of Theorem bi12imp3

Step	Hyp	Ref	Expression
1		bi12imp3.1	. . 3 ⊢ (𝜑 ↔ (𝜓 ↔ (𝜒 → 𝜃)))
2	1	biimpi 215	. 2 ⊢ (𝜑 → (𝜓 ↔ (𝜒 → 𝜃)))
3	2	bi23imp13 42000	1 ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) → 𝜃)

Syntax hints:   → wi 4   ↔ wb 205   ∧ w3a 1085

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 206  df-an 396  df-3an 1087

This theorem is referenced by: (None)