X²-Y²-X-Y 的值(分解因式)
问题描述:
X²-Y²-X-Y 的值(分解因式)
答
(x-y)(x+y)-(x+y)
=(x+y)(x-y-1)
答
(x-y)(x+y-1)
答
原式=(x+y)(x-y)-(x+y)
=(x+y)(x-y)-(x+y)x1 [可省略]
=(x+y)(x-y-1)