# Determine the radius of convergence of the given power series

Find the radius of convergence of the given power series:

$$\sum _{n=0}^{ \infty} \frac{(-1)^{n+9} (x-3)^{n+9}}{n+9}$$

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Do you also want people to post their answer, or just to determine it? I should also point that this is not a question. There is no WH-word, and there is no question mark at the end. –  Asaf Karagila Nov 17 '12 at 22:35
Hint: Note that this series has the same convergence radius as the following series: $$x^9\cdot\sum_{n=0}^\infty\frac{(-1)^{n+1} x^n}{n+9}$$