多项式x2y-y2z+z2x-x2z+y2x+z2y-2xyz因式分解后的结果是(  ) A.(y-z)(x+y)(x-z) B.(y-z)(x-y)(x+z) C.(y+z)(x-y)(x+z) D.(y+z)(x+y)(x-z)

问题描述:

多项式x2y-y2z+z2x-x2z+y2x+z2y-2xyz因式分解后的结果是(  )
A. (y-z)(x+y)(x-z)
B. (y-z)(x-y)(x+z)
C. (y+z)(x-y)(x+z)
D. (y+z)(x+y)(x-z)

x2y-y2z+z2x-x2z+y2x+z2y-2xyz
=(y-z)x2+(z2+y2-2yz)x+z2y-y2z
=(y-z)x2+(y-z)2x-yz(y-z)
=(y-z)[x2+(y-z)x-yz]
=(y-z)(x+y)(x-z).
故选A.