1. The problem statement, all variables and given/known data I am trying to represent the function 2x/(1+x2) as a series and determine its radius of convergence. 2. Relevant equations 3. The attempt at a solution Using the series for ln(1-x) I have come up with the following series: Ʃ(n=1,infinity) [2*(-1)n*x2n-1], with radius of convergence 1 (for 0<x<1). Could someone please confirm that this is indeed the correct answer?