Theorem 3bitr2d 215

Description: Deduction from transitivity of biconditional. (Contributed by NM, 4-Aug-2006.)

Hypotheses

Ref	Expression
3bitr2d.1	⊢ (𝜑 → (𝜓 ↔ 𝜒))
3bitr2d.2	⊢ (𝜑 → (𝜃 ↔ 𝜒))
3bitr2d.3	⊢ (𝜑 → (𝜃 ↔ 𝜏))

Assertion

Ref	Expression
3bitr2d	⊢ (𝜑 → (𝜓 ↔ 𝜏))

Proof of Theorem 3bitr2d

Step	Hyp	Ref	Expression
1		3bitr2d.1	. . 3 ⊢ (𝜑 → (𝜓 ↔ 𝜒))
2		3bitr2d.2	. . 3 ⊢ (𝜑 → (𝜃 ↔ 𝜒))
3	1, 2	bitr4d 190	. 2 ⊢ (𝜑 → (𝜓 ↔ 𝜃))
4		3bitr2d.3	. 2 ⊢ (𝜑 → (𝜃 ↔ 𝜏))
5	3, 4	bitrd 187	1 ⊢ (𝜑 → (𝜓 ↔ 𝜏))

Syntax hints:   → wi 4   ↔ wb 104

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107

This theorem depends on definitions:  df-bi 116

This theorem is referenced by:  ceqsralt  2739  frecsuclem  6353  indpi  7262  cauappcvgprlemladdru  7576  prsrlt  7707  lesub2  8332  ltsub2  8334  rec11ap  8583  avglt1  9071  rpnegap  9593  modqmuladdnn0  10267  expap0  10449  2shfti  10731  mulreap  10764  minmax  11129  lemininf  11133  xrminmax  11162  xrlemininf  11168  modremain  11819  nn0seqcvgd  11917  divgcdcoprm0  11977  isxmet2d  12748  xblss2  12805  neibl  12891  ellimc3apf  13029  logbgt0b  13283  iswomninnlem  13620