2x^2-xy-y^2-4x-5y-6
问题描述:
2x^2-xy-y^2-4x-5y-6
答
2x^2-xy-y^2-4x-5y-6
=(2x+y)(x-y)-4x-5y-6
=(2x+y+2)(x-y-3)
2x+y 2
x-y -3
十字相乘法