Question

把多项式x的平方减y的平方减2x减4y减3因式分解？

Answer 1

=(x+y)(x-y)-2x-4y-3
=(x+y)(x-y)+(x-y)-3x-3y-3
=(x-y)(x+y+1)-3(x+y+1)
=(x-y-3)(x+y+1),9,X^2-Y^2-2X-4Y-3
X^2-2X-1+4-4Y-Y^2
(X-1)^2+(4-2)^2
这就是最简形式了,1,第1种原式=x^2-2x+1-(y^2+4y+4)
=(x-1)^2-(y+2)^2
=(x-1+y+2)(x-1-y-2)
=(x+y+1)(x-y-3)
第2种原式=(x+y)(x-y)-2x-4y-3
=(x+y)(x-y)+(x-y)-3x-3y-3
=(x-y)(x+y+1)-3(x+y+1)
=(x-y-3)(x+y+1),0,........
怎么个就不能分解了呢。
原式=x^2-2x-y^2-4y-3
=x^-2x-(y+1)(y+3)
=（x-y-3)(x+y+1),0,