中国广告的发展史:分解因式!!!

来源:百度文库 编辑:高考问答 时间:2024/04/28 20:33:58
(x-y)^2-2x+2y+1

(x-y)^2-2x+2y+1
=x^2-2xy+y^2-2x+2y+1
然后用双十字相乘
=(x-y-1)(x-y-1)
=(x-y-1)^2

(X-Y-1)(X-Y-1)

(X-Y-1)^2

原式=(X-Y)^2-2(X-Y)+1=(X-Y-1)^2