y=10(x²-x/2)+2
=10(x²-x/2+1/16-1/16)+2
=10(x²-x/2+1/16)-5/8+2
=10(x-1/4)²+11/8
图像对称轴是:x=1/4
与x轴位置关系是:在x轴上方
与y轴交点坐标是:(0,2)