问题 填空题

因式分x2-y2-2x+1=______.

答案

x2-y2-2x+1,

=-y2+(x2-2x+1),

=-y2+(x-1)2

=(x+y-1)(x-y-1).

故答案为:(x+y-1)(x-y-1).

单项选择题
单项选择题