Results 1 to 10 of about 2,953 (263)
New Criteria for Univalent, Starlike, Convex, and Close-to-Convex Functions on the Unit Disk [PDF]
In the present paper, we introduce and investigate three interesting superclasses SD, SD* and KD of analytic, normalized and univalent functions in the open unit disk D.
Mohammad Reza Yasamian +2 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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Nonvanishing univalent functions III
In two previous papers [Math. Z. 170, 195-216 (1980; Zbl 0411.30010) and Ann. Univ. Mariae Curie-Skłodowska, Sect. A 36/37 (1982-83), 33-43 (1983; Zbl 0572.30020)] we studied the class \(S_ 0\) of functions f analytic, univalent, and nonvanishing in the unit disk D, with \(f(0)=1\).
Duren, Peter L. (1935- ) +1 more
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Coefficient Estimates for Certain Classes of Bi-Univalent Functions
A function analytic in the open unit disk is said to be bi-univalent in if both the function and its inverse map are univalent there. The bi-univalency condition imposed on the functions analytic in makes the behavior of their coefficients ...
Jay M. Jahangiri, Samaneh G. Hamidi
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On convolutions of slanted half-plane mappings
The convolution of convex harmonic univalent functions in the unit disk, unlike analytic functions, may not be convex or even univalent. The main purpose of this work is to develop previous work involving the convolution of convex harmonic functions ...
Elif Yaşar
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Subclasses of analytic and bi-univalent functions have been extensively improved and utilized for estimating the Taylor–Maclaurin coefficients and the Fekete–Szegö functional.
Abdulmtalb Hussen, Abdelbaset Zeyani
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Univalent functions having univalent derivatives [PDF]
Let T denote the family of functions \(f(z)=z-\sum^{\infty}_{n=2}a_ nz^ n\), \(a_ n\geq 0\), which are analytic and univalent in the unit disk \(\Delta =\{| z|
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On the Univalence Criterion of a General Integral Operator
In this paper we considered an general integral operator and three classes of univalent functions for which the second order derivative is equal to zero.
H. Özlem Güney, Daniel Breaz
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Univalent functions maximizing Re[f(ζ1)+f(ζ2)]
We study the problem maxh∈Sℜ[h(z1)+h(z2)] with z1,z2 in Δ. We show that no rotation of the Koebe function is a solution for this problem except possibly its real rotation, and only when z1=z¯2 or z1,z2 are both real, and are in a neighborhood of the x ...
Intisar Qumsiyeh Hibschweiler
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Remark on functions with all derivatives univalent
An attractive conjecture is discounted for the class of normalized univalent functions whose derivatives are also univalent.
M. Lachance
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