Theorem breq12i 3974

Description: Equality inference for a binary relation. (Contributed by NM, 8-Feb-1996.) (Proof shortened by Eric Schmidt, 4-Apr-2007.)

Hypotheses

Ref	Expression
breq1i.1	|- A = B
breq12i.2	|- C = D

Assertion

Ref	Expression
breq12i	|- ( A R C <-> B R D )

Proof of Theorem breq12i

Step	Hyp	Ref	Expression
1		breq1i.1	. 2 |- A = B
2		breq12i.2	. 2 |- C = D
3		breq12 3970	. 2 |- ( ( A = B /\ C = D ) -> ( A R C <-> B R D ) )
4	1, 2, 3	mp2an 423	1 |- ( A R C <-> B R D )

Syntax hints:   <-> wb 104   = wceq 1335   class class class wbr 3965

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1427  ax-7 1428  ax-gen 1429  ax-ie1 1473  ax-ie2 1474  ax-8 1484  ax-10 1485  ax-11 1486  ax-i12 1487  ax-bndl 1489  ax-4 1490  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2139

This theorem depends on definitions:  df-bi 116  df-3an 965  df-tru 1338  df-nf 1441  df-sb 1743  df-clab 2144  df-cleq 2150  df-clel 2153  df-nfc 2288  df-v 2714  df-un 3106  df-sn 3566  df-pr 3567  df-op 3569  df-br 3966

This theorem is referenced by:  3brtr3g  3997  3brtr4g  3998  caovord2  5993  ltneg  8337  leneg  8340  inelr  8459  lt2sqi  10506  le2sqi  10507