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Homework Help: Power Series Representation of xln(1+x^2)

  1. Nov 28, 2011 #1
    Write a power series representation of xln(1+x2)

    My first instinct was to attempt to take the second derivative and then find the summation and then integrate but that approach seemed to be a dead end. Basically, the x thrown in there confuses me and you can't split the function into two separate summations since one would not converge. Any hints..?
     
  2. jcsd
  3. Nov 28, 2011 #2
    Help, anyone?
     
  4. Nov 28, 2011 #3

    Dick

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    I assume you are expanding around x=0. The power series expansion of x is x. What's the power series expansion of ln(1+u) around u=0? Hence what's the power series expansion of ln(1+x^2). There is no double summation to worry about.
     
  5. Nov 28, 2011 #4
    I really need to put more thought into problems before posting here. Thanks, and I figured it out.
     
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