Case: (x−a)n(x-a)^n(x−a)n Use: P(x)(x−a)n=A1x−a+A2(x−a)2+⋯+An(x−a)n\frac{P(x)}{(x-a)^n}=\frac{A_1}{x-a}+\frac{A_2}{(x-a)^2}+\cdots+\frac{A_n}{(x-a)^n}(x−a)nP(x)=x−aA1+(x−a)2A2+⋯+(x−a)nAn Then solve by clearing denominators and comparing coefficients.