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Theorem ifbieq2d 3573
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 3570 . 2 (𝜑 → if(𝜓, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐴))
3 ifbieq2d.2 . . 3 (𝜑𝐴 = 𝐵)
43ifeq2d 3567 . 2 (𝜑 → if(𝜒, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐵))
52, 4eqtrd 2222 1 (𝜑 → if(𝜓, 𝐶, 𝐴) = if(𝜒, 𝐶, 𝐵))
Colors of variables: wff set class
Syntax hints:  wi 4  wb 105   = wceq 1364  ifcif 3549
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 615  ax-in2 616  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2171
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2176  df-cleq 2182  df-clel 2185  df-nfc 2321  df-rab 2477  df-v 2754  df-un 3148  df-if 3550
This theorem is referenced by:  difinfsnlem  7128  ctmlemr  7137  xnegeq  9857  xaddval  9875  iseqf1olemqval  10518  iseqf1olemqk  10525  seq3f1olemqsum  10531  exp3val  10553  gcdval  11992  gcdass  12048  lcmval  12095  lcmass  12117  pcval  12328  ennnfonelemj0  12452  ennnfonelemjn  12453  ennnfonelem0  12456  ennnfonelemp1  12457  ennnfonelemnn0  12473  mulgval  13064  znval  13932  lgsval  14863  lgsfvalg  14864  lgsval2lem  14869  nnsf  15213  peano4nninf  15214  peano3nninf  15215  exmidsbthr  15230
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