(x-y+1)^2-(x+y-3)^2

分类: 作业答案 • 2021-12-19 11:04:57

问题描述：

(x-y+1)^2-(x+y-3)^2

答

平方差公式得到：（2-2Y）(2X-2)提取2得到4（1-Y）(X+1)

答

(x-y+1)^2-(x+y-3)^2
=（x-y+1+x+y-3)(x-y+1-x-y+3)
=(2x-2)((4-2y)
=4(x-1)(2-y)

答

(x-y+1)^2-(x+y-3)^2
=[(x-y+1)+(x+y-3)]*[(x-y+1)-(x+y-3)]
=(x-2)(4-2y)
=2(x-2)(2-y)