x2+x+1-（-x）=（x+1）^2>=0,所以x2+x+1>=-x,又-x>-x-1,所以x2+x+1>=-x>-x-1
①y=0时,B={0,0,1},1>0,0=0,不符合x2+x+1>=-x>-x-1,舍去
②y>0时,-y<-(y/2)③y<0时,
⑴若-(y/2)<-y=⑵若-(y/2)⑶若y+1<-(y/2)<=-y,则y+1=-x-1,-(y/2)=-x,x=-2/3,y=-4/3,-y=4/3,x2+x+1=7/9,舍
x=1,y=2