zhè / dào / tí / xū yào / xiān / yòng / èr cì hán shù / qiú chū / pāo wù xiàn / de / dǐng diǎn / zuò biāo

这道题需要先用二次函数求出抛物线的顶点坐标。

This problem requires first using the quadratic function to find the vertex coordinates of the parabola.