9.Some properties on rectilinear generators of hyperboloid of one sheet are researched.The relation between rectilinear generators of hyperboloid of one sheet and its asymptotic cone are discussed.

• 摘要给出并证明?单叶双曲面的直母线的若干性质，讨论了单叶双曲面与其渐近锥面的直母线之间的关系。