ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  ifeq1d GIF version

Theorem ifeq1d 3543
Description: Equality deduction for conditional operator. (Contributed by NM, 16-Feb-2005.)
Hypothesis
Ref Expression
ifeq1d.1 (𝜑𝐴 = 𝐵)
Assertion
Ref Expression
ifeq1d (𝜑 → if(𝜓, 𝐴, 𝐶) = if(𝜓, 𝐵, 𝐶))

Proof of Theorem ifeq1d
StepHypRef Expression
1 ifeq1d.1 . 2 (𝜑𝐴 = 𝐵)
2 ifeq1 3529 . 2 (𝐴 = 𝐵 → if(𝜓, 𝐴, 𝐶) = if(𝜓, 𝐵, 𝐶))
31, 2syl 14 1 (𝜑 → if(𝜓, 𝐴, 𝐶) = if(𝜓, 𝐵, 𝐶))
Colors of variables: wff set class
Syntax hints:  wi 4   = wceq 1348  ifcif 3526
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 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-ext 2152
This theorem depends on definitions:  df-bi 116  df-tru 1351  df-nf 1454  df-sb 1756  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-rab 2457  df-v 2732  df-un 3125  df-if 3527
This theorem is referenced by:  ifeq12d  3545  ifbieq1d  3548  ifeq1dadc  3556  iseqf1olemjpcl  10451  iseqf1olemqpcl  10452  iseqf1olemfvp  10453  seq3f1olemqsum  10456  seq3f1olemp  10458  summodc  11346  fsum3  11350  fsum3ser  11360  isumlessdc  11459  prodeq2w  11519  prodmodc  11541  fprodseq  11546  prodssdc  11552  lgsval  13699
  Copyright terms: Public domain W3C validator