Theorem 3bitrrd 306

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

Hypotheses

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

Assertion

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

Proof of Theorem 3bitrrd

Step	Hyp	Ref	Expression
1		3bitrd.3	. 2 ⊢ (𝜑 → (𝜃 ↔ 𝜏))
2		3bitrd.1	. . 3 ⊢ (𝜑 → (𝜓 ↔ 𝜒))
3		3bitrd.2	. . 3 ⊢ (𝜑 → (𝜒 ↔ 𝜃))
4	2, 3	bitr2d 280	. 2 ⊢ (𝜑 → (𝜃 ↔ 𝜓))
5	1, 4	bitr3d 281	1 ⊢ (𝜑 → (𝜏 ↔ 𝜓))

Syntax hints:   → wi 4   ↔ wb 206

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 207

This theorem is referenced by:  rnmpt0f  6209  sbcoteq1a  8005  fnwelem  8083  mpocurryd  8221  compssiso  10296  divfl0  13756  cjreb  15058  cnpart  15175  bitsuz  16413  acsfn  17594  eqg0el  19124  ghmeqker  19184  odmulg  19497  psrbaglefi  21894  cnrest2  23242  hausdiag  23601  prdsbl  24447  mcubic  26825  2lgslem1a2  27369  fmptco1f1o  32723  qsidomlem2  33546  areacirclem4  37962  lmclim2  38009  cmtbr2N  39629  expdiophlem1  43378  cantnfresb  43681  rrx2linest  49102