Theorem nanbi12 1449

Description: Join two logical equivalences with anti-conjunction. (Contributed by SF, 2-Jan-2018.)

Assertion

Ref	Expression
nanbi12	⊢ (((𝜑 ↔ 𝜓) ∧ (𝜒 ↔ 𝜃)) → ((𝜑 ⊼ 𝜒) ↔ (𝜓 ⊼ 𝜃)))

Proof of Theorem nanbi12

Step	Hyp	Ref	Expression
1		nanbi1 1447	. 2 ⊢ ((𝜑 ↔ 𝜓) → ((𝜑 ⊼ 𝜒) ↔ (𝜓 ⊼ 𝜒)))
2		nanbi2 1448	. 2 ⊢ ((𝜒 ↔ 𝜃) → ((𝜓 ⊼ 𝜒) ↔ (𝜓 ⊼ 𝜃)))
3	1, 2	sylan9bb 732	1 ⊢ (((𝜑 ↔ 𝜓) ∧ (𝜒 ↔ 𝜃)) → ((𝜑 ⊼ 𝜒) ↔ (𝜓 ⊼ 𝜃)))

Syntax hints:   → wi 4   ↔ wb 195   ∧ wa 383   ⊼ wnan 1439

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 196  df-an 385  df-nan 1440

This theorem is referenced by:  nanbi12i  1452  nanbi12d  1455