1. The problem statement, all variables and given/known data What are the region of validity of the following? 1/[z2(z3+2)] = 1/z3 - 1/(6z) +4/z10 2. Relevant equations 3. The attempt at a solution Knowing that this is the expansion around z=0, I am trying to find the singularities of the complex function. Which is when z2(z3+2) = 0 I have z = 0, then (z3+2) = 0 (z3+2) = 0 z3 = -2 = r3ei3θ In order to find r, would I take the absolute value of z3? r = |z3| = |-2| = sqrt[(-2)2] = 2?