短语词组短语quartic manifold 四次廖circular quartic 圆点四次曲线space quartic 四次挠线nodal quartic 节点四次线tricuspidal quartic [数]三尖点四次线quartic systems 四次系统quartic spectrum 四次方谱quartic system 四次系统quartic equation 四次方程 返回 quartic