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Homework Help: Complex analysis taylor series Q

  1. Apr 7, 2006 #1
    hi, I'm wondering if someone can help me out with this question:

    "What are the first two non-zero terms of the Taylor series

    [tex]f(z) = \frac {sin(z)} {1 - z^4} [/tex] expanded about z = 0.

    (Don't use any differentiation. Just cross multiply and do mental arithmetic)"

    I know the formula for a Taylor series but I can't see how to do this with just cross multiplying and mental arithmetic.

  2. jcsd
  3. Apr 8, 2006 #2


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    This is a product of two functions: sin(z) and 1/(1-z^4).
    If you know the Taylor series of both, you can find their product by 'expanding the brackets'
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