Results 61 to 70 of about 101,039,394 (126)

Analytic functions close to mappings convex in one direction

, 1971
By analogy to the class of close-to-convex functions we define a class of analytic functions which are close to a family Σ \Sigma of mappings onto domains convex in one direction. In contrast to the close-to-convex class the close-to-
Glenn Schober, Walter Hengartner
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On the logarithmic coefficients of close to convex functions [PDF]

Proceedings of the American Mathematical Society, 2015
For $f$ analytic and close to convex in $D=\{z: |z|< 1\}$, we give sharp estimates for the logarithmic coefficients $γ_{n}$ of $f$ defined by $\log \dfrac{f(z)}{z}=2\sum_{n=1}^{\infty} γ_{n}z^{n}$ when $n=1, 2,3$.
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On subclasses of close-to-convex functions of higher order

International Journal of Mathematics and Mathematical Sciences, 1992
The classes Tk(ρ), 0 ...
Khalida Inayat Noor
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On close-to-convex functions

On close-to-convex functions
We consider a new subclass $\widetilde{\mathcal{K}}_u$ of close-to-convex functions in the unit disk $\mathbb{D}:=\{z\in\mathbb{C}:|z|<1\}$. For this class, we obtain sharp estimates of the Fekete-Szegö problem, growth and distortion theorem, radius of convexity and estimate of the pre-Schwarzian norm.
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Sharp Inequalities of Ostrowski Type for Convex Functions Defined on Linear Spaces and Applications [PDF]

, 2007
An Ostrowski type inequality for general convex functions defined on linear spaces is generalised. Some inequalities which improve the Hermite- Hadamard type inequality for convex functions defined on linear spaces are derived using the obtained ...
Dragomir, Sever S, Cerone, Pietro, Kikianty, Eder   +2 more
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A note on certain subclass of close-to-convex functions

International Journal of Mathematics and Mathematical Sciences, 1988
The object of the present paper is to show a result for functions belonging to class P′(1−α,0) which is a subclass of close-to-convex functions in the unit disk U.
Shigeyoshi Owa, Liu Liquan, Wancang Ma
doaj   +1 more source

The Effect of Transformations on the Approximation of Univariate (Convex) Functions with Applications to Pareto Curves [PDF]

In the literature, methods for the construction of piecewise linear upper and lower bounds for the approximation of univariate convex functions have been proposed.We study the effect of the use of increasing convex or increasing concave transformations ...
Siem, A.Y.D., Hertog, D. den, Hoffmann, A.L.   +2 more
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Close-to-convexity and Starlikeness of Analytic Functions

Tamkang Journal of Mathematics, 2015
For functions $f(z)=z^p+a_{n+1}z^{p+1}+\cdots$ defined on the open unit disk, the condition $RE (f'(z)/z^{p-1})>0$ is sufficient for close-to-convexity of $f$. By making use of this result, several sufficient conditions for close-to-convexity are investigated and relevant connections with previously known results are indicated.
Lee, See Keong, Ravichandran, V., Supramaniam, Shamani   +2 more
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Coefficient estimates for Libera type bi-close-to-convex functions

, 2021
In a very recent paper, Wang and Bulut [A note on the coefficient estimates of bi-close-to-convex functions, C. R. Acad. Sci. Paris, Ser. I 355 (2017), 876-880] determined the estimates for the general Taylor-Maclaurin coefficients of functions belonging
BULUT, SERAP
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Generalizations of p-valent functions via the hadamard product

International Journal of Mathematics and Mathematical Sciences, 1982
The classes of univalent prestarlike functions Rα, α≥−1, of Ruscheweyh [1] and a certain generalization of Rα were studied recently by Al-Amiri [2]. The author studies, among other things, the classes of p-valent functions R(α+p−1) where p is a positive ...
Anil K. Soni
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