Theorem 3anbi23d 1326

Description: Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)

Hypotheses

Ref	Expression
3anbi12d.1	⊢ (𝜑 → (𝜓 ↔ 𝜒))
3anbi12d.2	⊢ (𝜑 → (𝜃 ↔ 𝜏))

Assertion

Ref	Expression
3anbi23d	⊢ (𝜑 → ((𝜂 ∧ 𝜓 ∧ 𝜃) ↔ (𝜂 ∧ 𝜒 ∧ 𝜏)))

Proof of Theorem 3anbi23d

Step	Hyp	Ref	Expression
1		biidd 172	. 2 ⊢ (𝜑 → (𝜂 ↔ 𝜂))
2		3anbi12d.1	. 2 ⊢ (𝜑 → (𝜓 ↔ 𝜒))
3		3anbi12d.2	. 2 ⊢ (𝜑 → (𝜃 ↔ 𝜏))
4	1, 2, 3	3anbi123d 1323	1 ⊢ (𝜑 → ((𝜂 ∧ 𝜓 ∧ 𝜃) ↔ (𝜂 ∧ 𝜒 ∧ 𝜏)))

Syntax hints:   → wi 4   ↔ wb 105   ∧ w3a 980

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  df-3an 982

This theorem is referenced by:  ltxrlt  8092  dfgcd2  12181  issubg3  13322  ivthreinc  14881