求 2x^2-xy-y^2-x-2y-1 因式分解RT2x^2-xy-y^2-x-2y-1 因式分解3Q
问题描述:
求 2x^2-xy-y^2-x-2y-1 因式分解
RT
2x^2-xy-y^2-x-2y-1 因式分解
3Q
答
2x^2-xy-y^2-x-2y-1
=(2x+y)(x-y)-(x+2y)-1
=(2x+y+1)(x-y-1)
2x+y 1
x-y -1