(2x+3)÷[x(x-1)(x+2)]=A÷x+B÷(x-1)+C÷(x+2) 2x+3=A*(x-1)(x+2)+B*x(x+2)+C*x(x-1) 2x+3=A(x^2+x-2)+B(x^2+2x)+C(x^2-x) 2x+3=(A+B+C)x^2+(A+2B-C)x-2A A+B+C=0 A+2B-C=2 -2A=3 解方程组得：A=-3/2,B=5/3,C=-1/6...