Theorem sylan9bbr 436

Description: Nested syllogism inference conjoining dissimilar antecedents. (Contributed by NM, 4-Mar-1995.)

Hypotheses

Ref	Expression
sylan9bbr.1	⊢ (𝜑 → (𝜓 ↔ 𝜒))
sylan9bbr.2	⊢ (𝜃 → (𝜒 ↔ 𝜏))

Assertion

Ref	Expression
sylan9bbr	⊢ ((𝜃 ∧ 𝜑) → (𝜓 ↔ 𝜏))

Proof of Theorem sylan9bbr

Step	Hyp	Ref	Expression
1		sylan9bbr.1	. . 3 ⊢ (𝜑 → (𝜓 ↔ 𝜒))
2		sylan9bbr.2	. . 3 ⊢ (𝜃 → (𝜒 ↔ 𝜏))
3	1, 2	sylan9bb 435	. 2 ⊢ ((𝜑 ∧ 𝜃) → (𝜓 ↔ 𝜏))
4	3	ancoms 255	1 ⊢ ((𝜃 ∧ 𝜑) → (𝜓 ↔ 𝜏))

Syntax hints:   → wi 4   ∧ wa 97   ↔ wb 98

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101

This theorem depends on definitions:  df-bi 110

This theorem is referenced by:  pm5.75  869  mpteq12f  3837  opelopabsb  3997  elreimasng  4691  fvelrnb  5221  fmptco  5330  fconstfvm  5379  f1oiso  5465  mpt2eq123  5564  dfoprab4f  5819  fmpt2x  5826  nnmword  6091  ltmpig  6437  qreccl  8576  0fz1  8909  cbvrald  9927