在一个方向上凸的函数的截面的半径

IF 0.7 Q2 MATHEMATICS
Prachi Prajna Dash, Jugal Kishore Prajapat, Naveen Kumari
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引用次数: 0

摘要

设\({\mathcal {G}}(\alpha )\)表示开放单元磁盘\({\mathbb {D}} :=\{z\in {\mathbb {C}}: |z|<1\}\)中满足\(f(0)=0=f'(0)=1\)和$$\begin{aligned} \Re \left( 1+ \dfrac{zf''(z)}{f'(z)}\right) <1+\dfrac{\alpha }{2} , \quad z\in {\mathbb {D}}. \end{aligned}$$的函数族f(z)。我们确定在这些磁盘\(|z|<\rho _n\)中,f(z)的部分\(s_n(z;f)\)是凸的、星形的和接近于凸的\(\beta \;(0\le \beta < 1)\)级。进一步,在考虑的函数类中,我们得到了部分的若干不等式。
本文章由计算机程序翻译,如有差异,请以英文原文为准。

Radii for sections of functions convex in one direction

Radii for sections of functions convex in one direction

Radii for sections of functions convex in one direction

Let \({\mathcal {G}}(\alpha )\) denote the family of functions f(z) in the open unit disk \({\mathbb {D}} :=\{z\in {\mathbb {C}}: |z|<1\}\) that satisfy \(f(0)=0=f'(0)=1\) and

$$\begin{aligned} \Re \left( 1+ \dfrac{zf''(z)}{f'(z)}\right) <1+\dfrac{\alpha }{2} , \quad z\in {\mathbb {D}}. \end{aligned}$$

We determine the disks \(|z|<\rho _n\) in which sections \(s_n(z;f)\) of f(z) are convex, starlike, and close-to-convex of order \(\beta \;(0\le \beta < 1)\). Further, we obtain certain inequalities of sections in the considered class of functions.

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来源期刊
Afrika Matematika
Afrika Matematika MATHEMATICS-
CiteScore
2.00
自引率
9.10%
发文量
96
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