x^2-2xy+y^2-2x+2y+1

网友回答

x^2-2xy+y^2-2x+2y+1
=(x-y)^2-2(x-y)+1
=(x-y-1)^2
======以下答案可供参考======
供参考答案1:
x^2-2xy+y^2-2x+2y+1
=(x^2-2xy+y^2)-2x+2y+1
=(x-y)^2-2(x-y)+1
=(x-y-1)^2
供参考答案2:
x^2-2xy+y^2-2x+2y+1
=（x-y)^2-2(x-y)+1
=(x-y-1)^2