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Theorem ifbieq2d 3560
Description: Equivalence/equality deduction for conditional operators. (Contributed by Paul Chapman, 22-Jun-2011.)
Hypotheses
Ref Expression
ifbieq2d.1 (𝜑 → (𝜓𝜒))
ifbieq2d.2 (𝜑𝐴 = 𝐵)
Assertion
Ref Expression
ifbieq2d (𝜑 → if(𝜓, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐵))

Proof of Theorem ifbieq2d
StepHypRef Expression
1 ifbieq2d.1 . . 3 (𝜑 → (𝜓𝜒))
21ifbid 3557 . 2 (𝜑 → if(𝜓, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐴))
3 ifbieq2d.2 . . 3 (𝜑𝐴 = 𝐵)
43ifeq2d 3554 . 2 (𝜑 → if(𝜒, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐵))
52, 4eqtrd 2210 1 (𝜑 → if(𝜓, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐵))
Colors of variables: wff set class
Syntax hints:  wi 4  wb 105   = wceq 1353  ifcif 3536
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159
This theorem depends on definitions:  df-bi 117  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-rab 2464  df-v 2741  df-un 3135  df-if 3537
This theorem is referenced by:  difinfsnlem  7100  ctmlemr  7109  xnegeq  9829  xaddval  9847  iseqf1olemqval  10489  iseqf1olemqk  10496  seq3f1olemqsum  10502  exp3val  10524  gcdval  11962  gcdass  12018  lcmval  12065  lcmass  12087  pcval  12298  ennnfonelemj0  12404  ennnfonelemjn  12405  ennnfonelem0  12408  ennnfonelemp1  12409  ennnfonelemnn0  12425  mulgval  12991  lgsval  14444  lgsfvalg  14445  lgsval2lem  14450  nnsf  14793  peano4nninf  14794  peano3nninf  14795  exmidsbthr  14810
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