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Math Help - Radius of convergence

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    Radius of convergence

    What is the radius of convergence of the power series expansion of about ?

    Could someone explain how to claculate the ROC? Cheers.
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    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by Haris View Post
    What is the radius of convergence of the power series expansion of about ?

    Could someone explain how to claculate the ROC? Cheers.
    first find the series (which hopefully you can write in closed form) from there, the ratio test or the root test can help you find the ROC
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  3. #3
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    The power series for the numerator converges when |6x|<1. The power series for the denominator converges when |4x|<1. For the power series of the function as a whole to converge, you need both those conditions to hold.
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