I Coefficients in a quotient of sums

AI Thread Summary
The discussion focuses on finding the coefficient of the order \(x^j\) term in the quotient of two infinite power series. Participants suggest using polynomial long division as a method to derive the desired coefficient. An example from a provided resource illustrates this approach effectively. Although the process can be tedious, it is deemed successful for the user's needs. The conversation confirms that there is a systematic way to express the coefficient in question.
Sturk200
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Is there a general way to express, for instance, the coefficient of the order $x^j$ term in the expression

$$\frac{\Sigma_{n}^{\infty}a_nx^n}{\Sigma_{m}^{\infty}b_mx^m}$$ ?

Basically I am working with a quotient of two infinite power series and I want to know the term in this quotient that is proportional to a particular power of the expansion variable. Am I even guaranteed that there will be such a term? How do I find it?
 
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Sturk200 said:
Is there a general way to express, for instance, the coefficient of the order $x^j$ term in the expression

$$\frac{\Sigma_{n}^{\infty}a_nx^n}{\Sigma_{m}^{\infty}b_mx^m}$$ ?

You could try doing division, similar to the way that one divides one polynomial by another polynomial. There's an example on page 3 of http://www2.fiu.edu/~aladrog/IntrodPowerSeries.pdf
 
Stephen Tashi said:
You could try doing division, similar to the way that one divides one polynomial by another polynomial. There's an example on page 3 of http://www2.fiu.edu/~aladrog/IntrodPowerSeries.pdf

That was a bit tedious, but I think it actually worked for my purpose. Thanks!
 
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