设(ax^3-x+6)(3x^3+5x+b)=6x^5+10x^4-7x^3+13x^2+32x-12,求a与b的值.
问题描述:
设(ax^3-x+6)(3x^3+5x+b)=6x^5+10x^4-7x^3+13x^2+32x-12,求a与b的值.
答案是a=2,b=-2,求过程
答
设(ax^3-x+6)(3x^3+5x+b)=6x^6+10x^4-7x^3+13x^2+32x-12,
左边展后x^6项系数是3a,常数项是6b
右边多项式的x^6项系数是6,常数项是-12
所以有3a=6,6b=-12
a=2,b=-2