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Theorem 3bitr4d 276
Description: Deduction from transitivity of biconditional. Useful for converting conditional definitions in a formula. (Contributed by NM, 18-Oct-1995.)
Hypotheses
Ref Expression
3bitr4d.1
3bitr4d.2
3bitr4d.3
Assertion
Ref Expression
3bitr4d

Proof of Theorem 3bitr4d
StepHypRef Expression
1 3bitr4d.2 . 2
2 3bitr4d.1 . . 3
3 3bitr4d.3 . . 3
42, 3bitr4d 247 . 2
51, 4bitrd 244 1
Colors of variables: wff setvar class
Syntax hints:   wi 4   wb 176
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 177
This theorem is referenced by:  sbcom  2089  sbcom2  2114  r19.12sn  3789  lefinlteq  4463  eqtfinrelk  4486  tfinlefin  4502  opbrop  4841  fvopab3g  5386  unpreima  5408  inpreima  5409  respreima  5410  fconst5  5455  isotr  5495  ncseqnc  6128
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