Theorem imim12d 74

Description: Deduction combining antecedents and consequents. (Contributed by NM, 7-Aug-1994.) (Proof shortened by O'Cat, 30-Oct-2011.)

Hypotheses

Ref	Expression
imim12d.1	⊢ (𝜑 → (𝜓 → 𝜒))
imim12d.2	⊢ (𝜑 → (𝜃 → 𝜏))

Assertion

Ref	Expression
imim12d	⊢ (𝜑 → ((𝜒 → 𝜃) → (𝜓 → 𝜏)))

Proof of Theorem imim12d

Step	Hyp	Ref	Expression
1		imim12d.1	. 2 ⊢ (𝜑 → (𝜓 → 𝜒))
2		imim12d.2	. . 3 ⊢ (𝜑 → (𝜃 → 𝜏))
3	2	imim2d 54	. 2 ⊢ (𝜑 → ((𝜒 → 𝜃) → (𝜒 → 𝜏)))
4	1, 3	syl5d 68	1 ⊢ (𝜑 → ((𝜒 → 𝜃) → (𝜓 → 𝜏)))

Syntax hints:   → wi 4

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

This theorem is referenced by:  imim1d  75  equveli  1732  hbsb4t  1986  mo23  2038  rspcimdv  2785  r19.29uz  10757  txlm  12437  metcnpi3  12675  addcncntoplem  12709  cnplimcim  12794  setindis  13154  bdsetindis  13156  bj-findis  13166