y=(x³+1-1)/(x+1)
=(x³+1)/(x+1)-1/(x+1)
=(x²-x+1)(x+1)/(x+1)-1/(x+1)
=xN-x+1-1/(x+1)
1/(x+1)是整数
所以x+1=±1
x=0,x=-2
带入原式求出y即可