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Homework Help: Calculating exponent of complex number.

  1. Apr 10, 2012 #1
    1. The problem statement, all variables and given/known data

    z= 1+i√3
    find z^9


    2. Relevant equations



    3. The attempt at a solution

    Arg(z) = pi/3 and |z|=2


    so z= 2e^i*pi/3

    so z^9 = 2^9 (cos6pi +isin 6pi)

    = 512(1) =512
    but the answer has negative 512?
     
  2. jcsd
  3. Apr 10, 2012 #2

    SammyS

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    What is [itex]\displaystyle \left(2\,e^{i\pi/3}\right)^9\,?[/itex]
     
  4. Apr 10, 2012 #3
    512*(cos 3pi +isin3pi)

    = 512(-1) =-512

    THANKS!!!
     
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