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Thread: Find the roots of a complex number

  1. #1
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    Find the roots of a complex number

    [2(cos(pi/3)+isin(pi/3))]^(.5)

    I simplified it to 2^(.5) * (cos(pi/6)+isin(pi/6)), but I have no idea what else to go to.

    Any tips would be very helpful,
    thx in advance
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  2. #2
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    You have not simplified anything. You have demonstrated half of DeMoivre's formula. Now move on to the other half. You should find two solutions separated by $\displaystyle \pi$.
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  3. #3
    MHF Contributor

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    What are $\displaystyle sin(\pi/6)$ and $\displaystyle cos(\pi/6)$? You should be able to give exact values. ($\displaystyle \pi/6$ radians is the same as 30degreees.)
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