It says to find the Maclaurin series in sigma form and the interval on which it converges for
$\dfrac{7x^4}{2+3x^2} \qquad \text{if} \qquad \frac{1}{1-x} = \sum_{k=0}^{\infty}\, x^k, \;\; -1 \lt x \lt 1.$
I am confused as to what I'm supposed to do with the $\dfrac{7x^4}{2+3x^2}$. Am I supposed to take the derivative of that? And what is all that stuff to the right of it? I think that's to determine the interval which it converges on but I'm unsure.
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