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Math Help - Mind blank: Powers of complex numbers

  1. #1
    Senior Member
    Joined
    Apr 2010
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    487

    Mind blank: Powers of complex numbers

    The question:
    Evaluate (2 + 3i)^3

    If I remember correctly, the best way to do this is to convert to polar form, then apply the power. However, I'm getting crazy answers like 2035 - 828.02i

    Any assistance would be great!
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  2. #2
    Junior Member lanierms's Avatar
    Joined
    May 2010
    From
    Seoul, South Korea
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    50
    I don't know what polar form is. I think the best way to do it is just doing it.

    Solution:

    (2+3i)^2(2+3i)

    =(-5+12i)(2+3i)

    =-10-15i+24i-36

    =-46+9i
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  3. #3
    Senior Member
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    Fair enough, I guess I should do things the easy way. :P

    Thanks!
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