Theorem anabss1 679

Description: Absorption of antecedent into conjunction. (Contributed by NM, 20-Jul-1996.) (Proof shortened by Wolf Lammen, 31-Dec-2012.)

Hypothesis

Ref	Expression
anabss1.1	⊢ (((𝜑 ∧ 𝜓) ∧ 𝜑) → 𝜒)

Assertion

Ref	Expression
anabss1	⊢ ((𝜑 ∧ 𝜓) → 𝜒)

Proof of Theorem anabss1

Step	Hyp	Ref	Expression
1		anabss1.1	. . 3 ⊢ (((𝜑 ∧ 𝜓) ∧ 𝜑) → 𝜒)
2	1	an32s 665	. 2 ⊢ (((𝜑 ∧ 𝜑) ∧ 𝜓) → 𝜒)
3	2	anabsan 678	1 ⊢ ((𝜑 ∧ 𝜓) → 𝜒)

This proof depends on syntax axioms:   → wi 4   ∧ wa 401

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This proof depends on definitions:  df-bi 210  df-an 402

This theorem is used by:  anabss4  680  ordtri3or  6397  onfununi  8334  omordi  8557  oeoelem  8590  fzindd  12716  hashssdif  14469  nzss  45087  stirlinglem5  46852