Theorem imp4a 349

Description: An importation inference. (Contributed by NM, 26-Apr-1994.)

Hypothesis

Ref	Expression
imp4.1	⊢ (𝜑 → (𝜓 → (𝜒 → (𝜃 → 𝜏))))

Assertion

Ref	Expression
imp4a	⊢ (𝜑 → (𝜓 → ((𝜒 ∧ 𝜃) → 𝜏)))

Proof of Theorem imp4a

Step	Hyp	Ref	Expression
1		imp4.1	. 2 ⊢ (𝜑 → (𝜓 → (𝜒 → (𝜃 → 𝜏))))
2		impexp 263	. 2 ⊢ (((𝜒 ∧ 𝜃) → 𝜏) ↔ (𝜒 → (𝜃 → 𝜏)))
3	1, 2	imbitrrdi 162	1 ⊢ (𝜑 → (𝜓 → ((𝜒 ∧ 𝜃) → 𝜏)))

Syntax hints:   → wi 4   ∧ wa 104

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108

This theorem depends on definitions:  df-bi 117

This theorem is referenced by:  imp4b  350  imp4d  352  imp55  361  imp511  362  equs5or  1844  reuss2  3443  tfrlem9  6377  facwordi  10832  ndvdssub  12095  neibl  14727