1. The problem statement, all variables and given/known data Give the partial fraction decomposition of 1/z4+z2 2. Relevant equations 3. The attempt at a solution My question is about the final answer. The book gives the answer to be 1/z2+ 1/2i(z+i)- 1/2i(z-i). For my answer I keep getting a negative for both of the 1/2i coefficients, i.e my answer has a - where the book puts a +, and I can not for the life of me figure out what I am missing. My answer revolves around 1= A(z+i)(z-i)+ Bz2(z-i)+ Cz2(z+i) and then solving for the coefficients. How is B= 1/2i and not -(1/2i)?