English
Related papers

Related papers: On Coefficient problem for bi-univalent analytic f…

200 papers

In this work, we consider certain class of bi-univalent functions related with shell-like curves related to $\kappa-$Fibonacci numbers. Further, we obtain the estimates of initial Taylor-Maclaurin coefficients (second and third…

Complex Variables · Mathematics 2020-01-24 N. Magesh , J. Nirmala , J. Yamini

In this paper, we introduce two general subclasses of analytic functions by means of the principle of subordination and investigate the coefficient bounds for functions in theese classes. The well-known results are obtained as a corollary…

Complex Variables · Mathematics 2019-03-25 Serap Bulut

The Ruscheweyh derivative operator is used in this paper to introduce and investigate interesting general subclasses of the function class $\Sigma_{\mathrm{m}}$ of $m$-fold symmetric bi-univalent analytic functions. Estimates of the initial…

A univalent meromorphic function defined on $\Delta:= \{z \in \mathbb{C}: 1<|z|<\infty \}$ with univalent inverse defined on $\Delta$ is bi-univalent meromorphic in $\Delta$. For certain subclasses of meromorphic bi-univalent functions,…

Complex Variables · Mathematics 2011-08-23 Suzeini Abd Halim , Samaneh G. Hamidi , V. Ravichandran

In this work, the subclass of the function class S of bi-univalent functions associated with the quasi-subordination is defined and studied. Also some relevant classes are recognized and connections to previus results are made.

Complex Variables · Mathematics 2025-07-04 A. Akgul

In this work, considering a general subclass of bi-univalent functions and using the Chebyshev polynomials, we obtain coefficient expansions for functions in this class.

Complex Variables · Mathematics 2017-02-10 Sahsene Altinkaya , Sibel Yalcin

In this paper, we introduce and investigate a new subclass of the function class $\Sigma$ of bi-univalent functions defined in the open unit disk, which are associated with the S\u{a}l\u{a}gean type $q-$ difference operator and satisfy some…

Complex Variables · Mathematics 2017-10-03 G. Murugusundaramoorthy , K. Vijaya

In this paper, we introduce and investigate a new subclass of the function class $\Sigma$ of bi-univalent functions defined in the open unit disk, which are associated with the Hurwitz-Lerch zeta function, satisfying quasi-subordinate…

Complex Variables · Mathematics 2016-01-12 G Murugusundaramoorthy

For the real number $\alpha>1$, we use a technique due to Nehari and Netanyahu and an application of certain integral iteration of Caratheodory functions to find the best-possible upper bounds on the coefficients of functions of the class…

Complex Variables · Mathematics 2009-11-04 K. O. Babalola

In the present work, we propose to investigate the second Hankel determinant inequalities for certain class of analytic and bi-univalent functions. Some interesting applications of the results presented here are also discussed.

Complex Variables · Mathematics 2015-10-26 H. Orhan , N. Magesh , J. Yamini

In the present paper, we define a new general subclass of bi-univalent functions involving a differential operator in the open unit disk U. For this purpose, we use the Faber polynomial expansions. Several connections to some of the earlier…

Complex Variables · Mathematics 2018-11-20 Ala Amourah , Mohamed Illafe

In the present work, we propose to investigate the Fekete-Szeg\"o inequalities certain classes of analytic and bi-univalent functions defined by subordination. The results in the bounds of the third coefficient which improve many known…

Complex Variables · Mathematics 2014-04-04 Halit Orhan , N. Magesh , V. K. Balaji

Under certain conditions, we obtain sharp bounds on some functionals defined in the coefficient space of starlike functions. It has been found that the functionals are closely associated with certain coefficient problems, which are of…

Complex Variables · Mathematics 2009-10-23 K. O. Babalola

For $-1\le B<A\le 1$, let $\mathcal{S}^*(A,B)$ denote the class of normalized analytic functions $f(z)= z+\sum_{n=2}^{\infty}a_n z^n$ in $|z|<1$ which satisfy the subordination relation $zf'(z)/f(z)\prec (1+Az)/(1+Bz)$ and $\Sigma^*(A,B)$…

Complex Variables · Mathematics 2016-07-19 Md Firoz Ali , A. Vasudevarao

Some differential implications of classical Marx-Strohh\"acker theorem are extended for multivalent functions. These results are also generalized for functions with fixed second coefficient by using the theory of first order differential…

Complex Variables · Mathematics 2021-03-23 Prachi Gupta , Sumit Nagpal , V. Ravichandran

Recently, in their pioneering work on the subject of bi-univalent functions, Srivastava et al. \cite{HMS-AKM-PG} actually revived the study of the coefficient problems involving bi-univalent functions. Inspired by the pioneering work of…

Complex Variables · Mathematics 2018-10-16 N. Magesh , V. K. Balaji , C. Abirami

By considering a certain univalent function in the open unit disk U, that maps U onto a strip domain, we introduce a new class of analytic and close-to-convex functions by means of a certain non-homogeneous Cauchy-Euler-type differential…

Complex Variables · Mathematics 2019-02-19 Serap Bulut

In this paper, new class of bi-univalent functions are introduced. Upper bound of the second Hankel determinant $|H_2(2)|$ of subclass of bi-univalant functions class $\Sigma$, which defined by subordination, investigated. Furthermore, some…

Complex Variables · Mathematics 2019-08-21 Alaa H. El-Qadeem , Mohamed A. Mamon

In this paper we introduced the class $\mathcal{S}_{G}^{\ast }$ of analytic functions which is related with starlike functions and generating function of Gregory coefficients. By using bounds on some coefficient functionals for the family…

Complex Variables · Mathematics 2023-06-06 Sercan Kazımoğlu , Erhan Deniz , Hari Mohan Srivastava

In the present paper, a new subclass of analytic and bi-univalent functions by means of Chebyshev polynomials is introduced. Certain coefficient bounds for functions belong to this subclass are obtained. Furthermore, the Fekete-Szego…

Complex Variables · Mathematics 2021-02-18 Feras Yousef , B. A. Frasin , Tariq Al-Hawary