x²-3xy-10y²+x+9y-2如何分解因式
问题描述:
x²-3xy-10y²+x+9y-2如何分解因式
快啊,两点前要
答
x²-3xy-10y²=(x-5y)(x+2y)令x²-3xy-10y²+x+9y-2=(x-5y+A)(x+2y+B)即(x-5y+A)(x+2y+B)=(x-5y)(x+2y)+B(x-5y)+A(x+2y)+AB=x²-3xy-10y²+(A+B)x+(2A-5B)y+AB比较x²-3xy-10y²...