x^3+6x^2+3x-10
x=1时,x^3+6x^2+3x-10=0,所以有
x^3+6x^2+3x-10
=x²(x-1)+7x(x-1)+10(x-1)
=(x-1)(x²+7x+10）
=(x-1)(x+2)(x+5)