On sharp bounds of certain close-to-convex functions

被引：0

作者：

Goel, Priyanka ^{[1
]}

Kumar, S. Sivaprasad ^{[1
]}

机构：

[1] Delhi Technol Univ, Dept Appl Math, New Delhi 110042, India

来源：

AFRIKA MATEMATIKA | 2024年 / 35卷 / 02期

关键词：

Inverse coefficients; Close-to-convex functions; Univalent functions; Starlike functions; COEFFICIENT; INVERSES;

D O I：

10.1007/s13370-024-01176-7

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

We derive general formula for the fourth coefficient of the functions belonging to the Carath & eacute;odory class involving the parameters lying in the open unit disk. Further, we obtain sharp upper bounds of initial inverse coefficients for certain close-to-convex functions satisfying any one of the inequalities: Re((1 - z)f ' (z)) >0, Re((1 - z(2))f ' (z)) > 0, Re((1 - z + z(2))f '(z)) > 0 and Re((1-z)(2 )f ' (z)) > 0.

引用

页数：24

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