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Math Help - Question of complex power & cube roots

  1. #1
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    Question of complex power & cube roots

    Hi everyone,

    3+4i^(3/2) =
    z = 3 + 41
    z = 5(cos 0.9273 + isin0.9273 )
    z^(3/2) = 5^(3/2) = ( cos2((2pik + 0.273))/2 + isin2((2pik + 0.273))/2 )

    Is it correct? Pls advise,just wanted to confirm.

    Thank you & regards
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by anderson View Post
    Hi everyone,

    3+4i^(3/2) =
    z = 3 + 41
    z = 5(cos 0.9273 + isin0.9273 )
    z^(3/2) = 5^(3/2) = ( cos2((2pik + 0.273))/2 + isin2((2pik + 0.273))/2 )

    Is it correct? Pls advise,just wanted to confirm.

    Thank you & regards
    Try explaining what you are asking for and what you have done.

    (and guessing what you are trying to do, no it does not look right)

    CB
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  3. #3
    MHF Contributor

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    Quote Originally Posted by anderson View Post
    Hi everyone,

    3+4i^(3/2) =
    z = 3 + 41
    z = 5(cos 0.9273 + isin0.9273 )
    z^(3/2) = 5^(3/2) = ( cos2((2pik + 0.273))/2 + isin2((2pik + 0.273))/2 )
    You don't mean that last "=" do you? And you should be multiplying by "3" not "2".

    Is it correct? Pls advise,just wanted to confirm.

    Thank you & regards
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  4. #4
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    yup ur right, typo error.

    thanks.
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