Wyniki wyszukiwania - BazTech

1

On multivalent close-to-star functions

Singh Gagandeep, Singh Gurcharanjit

Fasciculi Mathematici

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2023

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nr 66

91--106

EN

The present paper deals with certain generalized subclasses of multivalent close-to-star functions defined with subordination. Various properties of these classes such as the coefficient estimates, growth theorems, argument theorems and inclusion relations are studied. Some earlier known results will follow as particular cases.

2

Radius problems for univalent functions

Sokół Janusz, Trąbka-Więcław Katarzyna

Journal of Applied Analysis

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2020

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Vol. 26, nr 1

111--115

EN

This paper considers the following problem: for what value r, r < 1 a function that is univalent in the unit disk |z| < 1 and convex in the disk |z| < r becomes starlike in |z| < 1. The number r is called the radius of convexity sufficient for starlikeness in the class of univalent functions. Several related problems are also considered.

3

Length problems for Bazilevič functions

Nunokawa Mamoru, Sokół Janusz, Tang Huo

Demonstratio Mathematica

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2019

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Vol. 52, nr 1

56--60

EN

Let C(r) denote the curve which is image of the circle |z|=r<1 under the mapping f. Let L(r) be the length of C(r) and A(r) the area enclosed by the curve C(r). Furthermore M(r) = max|z|=r |f(z)|. We present some relations between these notions for Bazilevič functions.

4

Coefficient conditions for univalency and starlikeness of analytic functions

Mondal S. R., Swaminathan A.

Journal of Mathematics and Applications

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2009

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Vol. 31

77-90

EN

In this paper, we find conditions on the coefficients {a(k)} such that the corresponding analytic function f(z) and its partial sum fn(z) are close-to-convex with respect to some starlike function in the unit disc D. We also find conditions on these coefficients so that the analytic function is starlike univalent in D. As an application, we find conditions on the triplet (a, b, c) so that, the normalized Gaussian hypergeometric function and its particular cases, are in one of these classes.

5

On certain subclasses of close-to-convex and

Wang Z-G., Jiang Y-P.

Journal of Mathematics and Applications

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2007

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Vol. 29

167-179

EN

In the present paper, the authors introduce two new subclasses S(sup k) (sub sc) (γ, α β) of close-to-convex functions and C(sup k) (sub sc) (γ, α β) of quasi-convex functions with respect to 2k-symmetric conjugate points. The inclusion and subordination relationships, convolution conditions for these classes are provided. The coefficient inequalities, integral representations and sufficient conditions for functions belonging to these classes are also provided.

6

Certain classes and inequalities and their applications to multivalently analytic functions

Dziok J., Irmak H.

Zeszyty Naukowe Politechniki Rzeszowskiej. Matematyka

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2001

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z. 25 [190]

55-62

EN

Using fractional calculus introduced by S. Owa we define two classes of analytic functions. Some sufficient conditions for functions to belong to these classes are given. Moreover consequences of main results are also pointed out.