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In this paper, it is a fuction that is a harmonically-convex differentiable for a new identity. As a result of this identity some new and general inequalities for differentiable harmonically-convex functions are obtained.

Classical Analysis and ODEs · Mathematics 2016-01-26 İmdat İşcan , Sercan Turhan , Selahattİn Maden

The classical Hurwitz theorem says that if n first "harmonics" (2n + 1 Fourier coefficients) of a continuous function f(x) on the unit circle are zero, then f(x) changes sign at least 2n + 1 times. We show that similar facts and its…

Metric Geometry · Mathematics 2009-04-27 Oleg R. Musin

This paper treats the class of normalized logharmonic mappings f(z) = zh(z)bar{g(z)} in the unit disk satisfying {\phi}(z) = zh(z)g(z) is analytically typically real. Every such mapping f is shown to be a product of two particular…

Complex Variables · Mathematics 2017-10-05 Najla M. Alarifi , Zayid Abdulhadi , Rosihan M. Ali

In this paper, we introduce the notion of conditional $h$-convex functions and we prove an operator version of the Jensen inequality for conditional $h$-convex functions. Using this type of functions, we give some refinements for Ky-Fan's…

Functional Analysis · Mathematics 2022-10-11 Ismail Nikoufar , Davuod Saeedi

This paper investigates positive harmonic functions on a domain which contains an infinite cylinder, and whose boundary is contained in the union of parallel hyperplanes. (In the plane its boundary consists of two sets of vertical…

Classical Analysis and ODEs · Mathematics 2010-10-04 Joanna Pres

In this article, we present univalence criteria for polyharmonic and polyanalytic functions. Our approach yields new a criterion for a polyharmonic functions to be fully $\alpha$--accessible. Several examples are presented to illustrate the…

Complex Variables · Mathematics 2016-12-08 K. F. Amozova , E. G. Ganenkova , S. Ponnusamy

Let $ \mathcal{H}(\Omega) $ be the class of complex-valued functions harmonic in $ \Omega\subset\mathbb{C} $ and each $f=h+\overline{g}\in \mathcal{H}(\Omega)$, where $ h $ and $ g $ are analytic. In the study of Bohr phenomenon for certain…

Complex Variables · Mathematics 2024-02-20 Molla Basir Ahamed , Partha Pratim Roy

In this present investigation, we found a set of sufficient conditions to be imposed on the parameters of the Fox H-functions which allow us to conclude that it is non-negative. As applications, various new facts regarding the Fox-Wright…

Classical Analysis and ODEs · Mathematics 2020-09-08 Khaled Mehrez

A motivation comes from {\em M. Ismail and et al.: A generalization of starlike functions, Complex Variables Theory Appl., 14 (1990), 77--84} to study a generalization of close-to-convex functions by means of a $q$-analog of a difference…

Complex Variables · Mathematics 2015-04-02 S. K. Sahoo , N. L. Sharma

Let be F a family of curves in the unit disc. We show that the set of all functions f holomorphic on the unit disc, which satisfy the following condition, is G-delta and dense in the space of all functions holomorphic on the unit disc: For…

Complex Variables · Mathematics 2007-05-23 Daniel Mayenberger

This research aimed to introduce the concept of harmonically m-convex set-valued functions, which is obtained from the combination of two definitions: harmonically m-convex functions and set-valued functions. In this work some properties…

Functional Analysis · Mathematics 2022-01-20 Gabriel Santana , Maira Valera-López

A normalized univalent function is uniformly convex if it maps every circular arc contained in the open unit disk with center in it into a convex curve. This article surveys recent results on the class of uniformly convex functions and on…

Complex Variables · Mathematics 2011-08-23 R. M. Ali , V. Ravichandran

Let $U\subseteq\mathbb{R}^d$ be open and convex. We prove that every (not necessarily Lipschitz or strongly) convex function $f:U\to\mathbb{R}$ can be approximated by real analytic convex functions, uniformly on all of $U$. We also show…

Differential Geometry · Mathematics 2014-10-24 Daniel Azagra

In this paper we first consider another version of the Rogosinski inequality for analytic functions $f(z)=\sum_{n=0}^\infty a_nz^n$ in the unit disk $|z| < 1$, in which we replace the coefficients $a_n$ $(n= 0,1,\ldots ,N)$ of the power…

Complex Variables · Mathematics 2020-04-21 Seraj A. Alkhaleefah , Ilgiz R. Kayumov , Saminathan Ponnusamy

Let $U\subseteq\mathbb{R}^{n}$ be open and convex. We show that every (not necessarily Lipschitz or strongly) convex function $f:U\to\mathbb{R}$ can be approximated by real analytic convex functions, uniformly on all of $U$. In doing so we…

Functional Analysis · Mathematics 2012-01-17 D. Azagra

In this paper necessary and sufficient conditions are deduced for the close-to-convexity of some special combinations of Bessel functions of the first kind and their derivatives by using a result of Shah and Trimble about transcendental…

Classical Analysis and ODEs · Mathematics 2017-07-14 Árpad Baricz , Erhan Deniz , Nihat Yagmur

A sequence of points $z_k$ in the unit disk is said to be thin for a given decrease function $\rho$, if there is a nontrivial bounded holomorphic function such that the infinite series $\sum_k \rho(1-|z_k|)|f(z_k)|$ converges. All sequences…

Complex Variables · Mathematics 2007-05-23 Vladimir Ya. Eiderman , Pascal J. Thomas

We introduce a fairly general concept of functional equation for $k$-tuples of functions $f_1,\dots,f_k\colon X \to Y$ between arbitrary sets. The homomorphy equations for mappings between groups and other algebraic systems, as well as…

Functional Analysis · Mathematics 2015-10-19 Pavol Zlatoš

In this paper, we investigate two subclasses of analytic and univalent functions associated with the exponential mapping $\varphi(z)=e^{\alpha z},\qquad 0<\alpha\le1,$ defined via the subordination conditions $\frac{zf'(z)}{f(z)}\prec…

Complex Variables · Mathematics 2026-05-29 Shantanu Panja , Sujoy Majumder , Abhijit Banerjee

The aim of this paper is to obtain the Schwarz-Pick type inequality for $\alpha$-harmonic functions $f$ in the unit disk and get estimates on the coefficients of $f$. As an application, a Landau type theorem of $\alpha$-harmonic functions…

Complex Variables · Mathematics 2017-05-30 Peijin Li , Xiantao Wang , Qianhong Xiao
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