Theorem 3ancoma 926

Description: Commutation law for triple conjunction. (Contributed by NM, 21-Apr-1994.)

Assertion

Ref	Expression
3ancoma	⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) ↔ (𝜓 ∧ 𝜑 ∧ 𝜒))

Proof of Theorem 3ancoma

Step	Hyp	Ref	Expression
1		ancom 262	. . 3 ⊢ ((𝜑 ∧ 𝜓) ↔ (𝜓 ∧ 𝜑))
2	1	anbi1i 445	. 2 ⊢ (((𝜑 ∧ 𝜓) ∧ 𝜒) ↔ ((𝜓 ∧ 𝜑) ∧ 𝜒))
3		df-3an 921	. 2 ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) ↔ ((𝜑 ∧ 𝜓) ∧ 𝜒))
4		df-3an 921	. 2 ⊢ ((𝜓 ∧ 𝜑 ∧ 𝜒) ↔ ((𝜓 ∧ 𝜑) ∧ 𝜒))
5	2, 3, 4	3bitr4i 210	1 ⊢ ((𝜑 ∧ 𝜓 ∧ 𝜒) ↔ (𝜓 ∧ 𝜑 ∧ 𝜒))

Syntax hints:   ∧ wa 102   ↔ wb 103   ∧ w3a 919

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106

This theorem depends on definitions:  df-bi 115  df-3an 921

This theorem is referenced by:  3ancomb  927  3anrev  929  3anan12  931  3com12  1142  elfzmlbp  9143  elfzo2  9160