x^4-3xy-10y^2+x+9y-2
问题描述：
x^4-3xy-10y^2+x+9y-2
答
x*后面的4是啥意思 是次数么 其他几个也是这个意思么
答
添项、拆项,得
x^2-3xy-10y^2+x+9y-2
=(x+2y)(x-5y)+2x+4y-x+5y-2
=(x+2y)(x-5y)+2(x+2y)-(x-5y+2)
=(x+2y)(x-5y+2)-(x-5y+2)
=(x+2y-1)(x-5y+2)