Results 21 to 30 of about 613 (189)
This paper is interested in certain subclasses of univalent and bi-univalent functions concerning to shell- like curves connected with k-Fibonacci numbers involving modified Sigmoid activation function θ(t)=2/(1+e^(-t) ) ,t ≥0 in unit disk
Amal Madhi Rashid, Abdul Rahman S. Juma
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On the class of bi-univalent functions
In an attempt to answer the question raised by A.W. Goodman, we obtain a covering theorem, a distortion theorem, a growth theorem, the radius of convexity and an argument estimate of f
Sivasubramanian, Srikandan +3 more
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Bounds for the Second Hankel Determinant of a General Subclass of Bi-Univalent Functions [PDF]
The Hankel determinant, which plays a significant role in the theory of univalent functions, is investigated here in the context of bi-univalent analytic functions.
Mohamed Illafe +3 more
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On Some New Classes of Bi-univalent Functions
Abstract In the present paper, we introduce and investigate two new subclasses Q Σ (n; y;k) and B Σ (n;β;k) of bi-valent functions in the unit disk U.
Darus, M., Singh, Saumya
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Coefficient estimates for certain subclass of bi-univalent functions [PDF]
In this paper, a subclass of bi-univalent functions is introduced using subordination. Estimates on the initial coefficients and the Fekete-Szego inequality are determined for functions in this subclass. The results would generalize the previous related works of several earlier authors.
Nurdiana Nurali +2 more
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Faber Polynomial Coefficient Estimates for Meromorphic Bi-Starlike Functions
We consider meromorphic starlike univalent functions that are also bi-starlike and find Faber polynomial coefficient estimates for these types of functions. A function is said to be bi-starlike if both the function and its inverse are starlike univalent.
Samaneh G. Hamidi +2 more
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Estimates of Initial Coefficients for Bi-Univalent Functions [PDF]
We consider the Fekete-Szegö inequalities for classes which were defined by Murugusundaramoorthy et al. (2013). These inequalities will result in bounds of the third coefficient which are better than these obtained by Murugusundaramoorthy et al. (2013). Moreover, we discuss two other classes of bi-univalent functions.
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Estimates of Coefficients for Bi-Univalent Functions in the Subclass H_∑ (n,γ,φ)
Considering that finding the bounds for the coefficients of the Taylor-Maclaurin series expansion of bi-univalent functions is one of the important subjects in geometric function theory that has attracted the attention of many researchers in the last ...
Khalid I. Abdullah , Nafya H. Mohammed
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In this investigation, by using the Komatu integral operator, we introduce the new class of bi-univalent functions based on the rule of subordination. Moreover, we use the Faber polynomial expansions and Fibonacci numbers to derive bounds for the general
Şahsene Altınkaya +2 more
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Bi-Univalent Function Classes Defined by Using a Second Einstein Function
Motivated by q-calculus, subordination principle, and the second Einstein function, we define two families of bi-univalent analytic functions on the open unit disc of the complex plane. We deduce estimates for the first two Maclaurin’s coefficients and the Fekete-Sezgö functional inequalities for the functions that belong to these families of functions.
Alaa H. El-Qadeem +2 more
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