I'm trying to find the interval of convergence:

$\displaystyle f(x) = \sum^ \infty_ {n=0} \frac{(-1)^{n+1}(x-1)^{n+1}}{n+1} = \mid x-1 \mid$

I still don't know how to find its interval of convergence. Could you explain the process to me? I really want to understand this concept before my final test on Monday. Thank you.