Theorem orcoms 742

Description: Commutation of disjuncts in antecedent. (Contributed by NM, 2-Dec-2012.)

Hypothesis

Ref	Expression
orcoms.1	⊢ ((𝜑 ∨ 𝜓) → 𝜒)

Assertion

Ref	Expression
orcoms	⊢ ((𝜓 ∨ 𝜑) → 𝜒)

Proof of Theorem orcoms

Step	Hyp	Ref	Expression
1		pm1.4 739	. 2 ⊢ ((𝜓 ∨ 𝜑) → (𝜑 ∨ 𝜓))
2		orcoms.1	. 2 ⊢ ((𝜑 ∨ 𝜓) → 𝜒)
3	1, 2	syl 14	1 ⊢ ((𝜓 ∨ 𝜑) → 𝜒)

This proof depends on syntax axioms:   → wi 4   ∨ wo 720

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721

This proof depends on definitions:  df-bi 117

This theorem is used by:  olcs  748  dcn  854  xorbin  1433  19.33b2  1682  r19.30dc  2698  pwssunim  4429  omnimkv  7496