把多项式2xy-x²-y+1²分解因式的结果是A(x-y+1)(y-x+1) B (x+y-1)(y-x+1) C(x+y-1)(x-y+1) D(x-y+1)(x-y--1)

问题描述:

把多项式2xy-x²-y+1²分解因式的结果是
A(x-y+1)(y-x+1) B (x+y-1)(y-x+1) C(x+y-1)(x-y+1) D(x-y+1)(x-y--1)

2xy-x²-y+1²
=-(x-y)²+1
=(1+x-y)(1-x+y)
所以选A
祝开心