Question

一道因式分解题 帮帮忙 2x²+xy-y²-4x+5y-6

Answer 1

原式=(2x-y)(x+y)-6x+3y+2x-2y-6
=(2x-y)(x+y)-3(2x-y)+2x-2y-6
=(2x-y)(x+y-3)+2(x+y-3)
=(x+y-3)(2x-y+2)

Answer 2

2x^2+xy-y^2-4x+5y-6
=(2x-y)(x+y)-4x+5y-6
=(2x-y)(x+y)+(2x+2y)-6x+3y-6
=(2x-y)(x+y)+2(x+y)-6x+3y-6
=(x+y)(2x-y+2)-3(2x-y+2)
=(x+y-3)(2x-y+2)