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Homework Help: Power Series

  1. Nov 29, 2007 #1
    1. The problem statement, all variables and given/known data

    The function [tex]f(x)=5xarctan(3x)[/tex] is represented as a power series. Find the first few coefficients in the power series.

    2. Relevant equations

    The power series is represented in the form [tex]sum(Cn*x^n)[/tex]

    3. The attempt at a solution

    I've attempted to write the function as an integral, and split the 5x with the trignonometric component. After doing this (and writing a power series), I'm not getting the right answer. Is something wrong with my approach?

    Thank you in advance.
  2. jcsd
  3. Nov 29, 2007 #2


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    Homework Helper

    Take f(x)=tan[itex]^{-1}[/itex]x and find the taylor series of it at [itex]\alpha=0[/itex] and the replace x by 3x and multiply by 5x after
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