x^4-2x^3+2x^2-x-6=0(x^3)(x-2)+(2x+3)(x-2)=0(x-2)(x^3+2x+3)=0有：x-2=0………………………(1)和：x^3+2x+3=0………………(2)由(1)得：x=2由(2)得：x^3+1+2x+2=0(x+1)(x^2-x+1)+2(x+1)=0(x+1)(x^2-x+3)=0有：x+1=0...