若多项式x²-2(kx-1)y+xy-x+y²不含xy的项,求k的值

问题描述:

若多项式x²-2(kx-1)y+xy-x+y²不含xy的项,求k的值

x²-2(kx-1)y+xy-x+y²
=x²-2kxy-y+xy-x+y²
-2k+1=0
2k=1
k=0.5