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Set theory help please !

  1. Oct 15, 2012 #1
    1. The problem statement, all variables and given/known data

    A = { pi + 2k pi / k [itex]\in[/itex] Z }
    B = {(- pi / 3) + (2k pi / 3 ) / k [itex]\in[/itex] A }
    Prove that A C B
    2. Relevant equations
    A C B = [itex]\forallX[/itex]E E : x [itex]\ni[/itex] A [itex]\Rightarrow[/itex] X [itex]\ni B[/itex]

    3. The attempt at a solution
    [itex]\ni[k E Z ][/itex]: x = pi + 2k pi
    [itex]\ni[k E Z ][/itex]: x = pi ( 1 + 2k)
    i'm sure i need to get a k and replace it with k' to prove that it belongs to B
  2. jcsd
  3. Oct 15, 2012 #2
    Edit : solved it by replacing pi by -pi/3+4pi/3 which led to the correct answer.
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