下面是某同学做的几道因式分解题,其中做对的是( )
| A.x2-2x+1=x(x-2)+1 | B.x2y2-1=(x+1)(y-1) |
| C.-4x2+y2=-(2x-y)2 | D.-x2-2ax-a2=-(x+a)2 |
| A.x2-2x+1=x(x-2)+1 | B.x2y2-1=(x+1)(y-1) |
| C.-4x2+y2=-(2x-y)2 | D.-x2-2ax-a2=-(x+a)2 |