数学物理学报

• 论文 • 上一篇    下一篇

具有缺项系数的几类解析函数族的性质

彭志刚   

  1. (湖北大学数学与计算机科学学院 武汉 430062)
  • 收稿日期:2007-01-15 修回日期:2008-05-15 出版日期:2008-08-25 发布日期:2008-08-25
  • 通讯作者: 彭志刚
  • 基金资助:
    国家自然科学在金(10771053)资助

The Properties of Several Classes of Analytic Functions with Missing Coefficients

Peng Zhigang   

  1. (College of Mathematics and Computer Science, Hubei University, Wuhan 430062)
  • Received:2007-01-15 Revised:2008-05-15 Online:2008-08-25 Published:2008-08-25
  • Contact: Peng Zhigang

摘要: S*表示所有在单位圆盘 D 内解析且满足条件 f(0)=f′ (0)-1=0的星形函数族, K 表示所有在 D内解析且满足条件 f(0)=f′ (0)-1=0 的凸函数族, P 表示所有在 D 内解析且满足条件p(0)=1, Rep(z)>0 的函数族. 设Pn={p(z): p(z)=1+anzn+an+1zn+1+…∈ P}, S*n={f (z): f(z)=z+anzn+an+1zn+1+…∈ S*}, Kn={f (z): f (z)=z+anzn+an+1zn+1+…∈ K}. LSn*={g(z)=ln f(z)/z, f ∈ Sn*}, 其中对数函数取使得ln1=0的那个单值解析分支. 该文研究了函数族Sn*, KnLSn*的性质, 找出了解析函数族LSn*的极值点与支撑点,并对S*nKn的极值点和支撑点作了一些探讨.

关键词: 闭一致收敛拓扑, 极值点, 支撑点

Abstract: Let A be the class of functions, which are analytic in the unit disc D={z:|z|<1}, with f (0)=f′(0)-1=0. Let S* be the set of starlike functions, S*={f (z)∈A, Re zf′(z) / f(z)>0, z D}. Let K be the set of convex functions, K={f(z) ∈ A, Re(1+zf’’(z) / f ’(z)>0, z∈ D}. P denotes the class of functions p(z), which are analytic in D and satisfy p(0)=1, Rep(z)>0. Let Pn={p(z): p(z)=1+anzn+an+1zn+1+… ∈ P}, S*n={f (z): f(z)=z+anzn+an+1zn+1+… ∈ S*}, Kn={ f(z): f (z)=z+anzn+an+1zn+1+ … ∈K}. LSn*={g(z)=ln f(z) / z, f ∈ Sn*}, where the logarithmic function satisfy ln1=0. In this article the author investigated the properties of the classes S*n, Kn and LSn*. The author obstained the extreme points and support points of LSn*, and discussed the extreme points and support points of S*n and Kn.

Key words: Topology of uniform convergence, Extreme point, Support point

中图分类号: 

  • 30C45