请问x3-6x2+ax+b=(x-1)(x-3)(?)a=?b=?
问题描述:
请问x3-6x2+ax+b=(x-1)(x-3)(?)a=?b=?
答
x3-6x2+ax+b=(x-1)(x-3)(cx+d)=(x^2-4x+3)(cx+d)=cx^3+dx^2-4cx^2-4dx+3cx+3d
c=1 d-4c=-6 -4d+3c=a 3d=b
c=1 d=-2 b=-6 a=11