问题 选择题

把x2+2xy+y2-1分解因式的结果是[ ]

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

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

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

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

答案

答案:A

单项选择题
单项选择题