(x^2+ax+b)*(x+2)=x^3+2x+12,求ab的值

(x^2+ax+b)*(x+2)=x^3+2x+12,求ab的值
(x^2+ax+b)*(x+2)=x^3+2x+12,求ab的值

(x^2+ax+b)*(x+2)=x^3+2x+12,求ab的值
(x^2+ax+b)*(x+2) =x^3+(a+2)x^2+(2a+b)x+2b 所以 a+2=0 2a+b=2 2b=12 解得 a=-2 b=6 ab=-12