HW Helper P: 3,307 maybe it would help if you gave the rational function you're attempting to write a laurent series for & about which point & region you want it to be convergent... along with what you've tried, otherwise i don't know exactly what it is you're asking click on tex code below to see how to write it, they open & close with the tags "tex" & "/tex" in [] brackets... eg to write a fraction use \frac{}{} $$f(z) = \frac{1}{(z-c)^2}$$ or $$f(z) = \sum_{-\infty}^{\infty} a_n (z-c)^n}$$
 P: 3 About Laurent series... Yeah, I'm sorry, I'm asked to find the laurent series of $$f(z) = \frac{1}{(2-z)^2(1-z)^2}$$ in two rings: 1<|z|<2 and |z|>2. Using partial fractions I got $$f(z) = \frac{-2}{1-z} + \frac{1}{(1-z)^2} + \frac{2}{2-z} + \frac{1}{(2-z)^2}$$ and I can easily obtain the laurent series in both rings of the first and third partial fraction, but I'm stuck in the other two! By the way, thanks!