Turkish Journal of Science
Journal license

Journal

Turkish Journal of Science


Volume
& Issue

Volume 8, Issue 2


Published
on

September 3, 2023


Pages

93-101


DOI

Article

Coefficient Estimates and Fekete-Szego Problem for Certain Subclass of Analytic and Univalent Functions Associated with Cosine and Sine Functions of Complex Order

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Authors

Nizami Mustafa Affiliation:
Kafkas University, Faculty of Science and Letters, Department of Mathematics, Kars, Turkey
and Veysel Nezir Affiliation:
Kafkas University, Faculty of Science and Letters, Department of Mathematics, Kars, Turkey


Abstract

The main focus of this paper is to give some coefficient estimates for the analytic and univalent functions on the open unit disk in the complex plane that are subordinated to cosine and sine functions with complex order. For the defined three subclasses of analytic and univalent functions S*(s_cos,sin ∈ C_cos,sin)(τ, β), τ ∈ C − {0} and β ∈ [0,1], satisfying a certain subordination condition to cos z + sin z, we obtain the coefficient estimates for the initial two coefficients and examine the Fekete-Szego problem for the mentioned class.


Keywords

Starlike function, convex function, cosine function, sine function, coefficient estimate, Fekete-Szego problem, complex.


Citation

Mustafa, N. & Nezir, V. (2023). Coefficient estimates and fekete-szego problem for certain subclass of analytic and univalent functions associated with cosine and sine functions of complex order. Turkish Journal of Science, 8(2), 93–101. https://doi.org/10.66833/TJOS-2023-0010

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