The function f (x) = 1 / (x2-x-6) is expanded into a power series of X

The function f (x) = 1 / (x2-x-6) is expanded into a power series of X

f(x)=1/(x-3)(x+2)=(1/5){[1/(x-3)]-[1/(x+2)]}=(1/5){[(-1/3)/(1-x/3)]-[(1/2)/(1+x/2)]}
=(1/5){(-1/3)∑(x/3)^n-(1/2)∑(-x/2)^n}=-1/15∑[(1/3)^n-(-1/2)^n]x^n
(-2