Results 31 to 40 of about 21,534 (315)
A class of univalent functions [PDF]
f'(0)= 1. In this paper we study the subclass denoted by F and defined by the condition If'(z) - Ij < 1 for I zj < 1.
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On a class of univalent functions [PDF]
We consider the class of univalent functions defined by the conditions f(z)/z ≠ 0 and |(z/f(z))′′| ≤ α, |z| < 1, where f(z) = z + ⋯ is analytic in |z| < 1 and 0 < α ≤ 2.
Dinggong Yang, Jin-Lin Liu
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On the Univalence of Poly-analytic Functions [PDF]
A continuous complex-valued function $F$ in a domain $D\subseteq\mathbf{C}$ is Poly-analytic of order $ $ if it satisfies $\partial^ _{\overline{z}}F=0.$ One can show that $F$ has the form $F(z)={\displaystyle\sum\limits_{0}^{n-1}}\overline{z}^{k}A_{k}(z)$, where each $A_k$ is an analytic function$.$ In this paper, we prove the existence of a Landau ...
Layan El Hajj, Zayid Abdulhadi
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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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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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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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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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Nonvanishing univalent functions [PDF]
The class S of functions g(z) = z + c 2 z 2 + c 3 z 3 + ... analytic and univalent in the unit disk Izr < 1 has been thoroughly studied, and its properties are well known. Our purpose is to investigate another class of functions which, by contrast, seems to have been rather neglected. This is the class S o of functions f ( z ) = 1 + a 1 z + a 2 z Z + .
Duren, Peter L., Schober, Glenn
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Boundary distortion estimates for holomorphic maps
We establish some estimates of the the angular derivatives from below for holomorphic self-maps of the unit disk at one and two fixed points of the unit circle provided there is no fixed point inside the unit disk. The results complement Cowen-Pommerenke
Frolova, A.+3 more
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Schwarzian Derivatives and Uniform Local Univalence
Quantitative estimates are obtained for the (finite) valence of functions analytic in the unit disk with Schwarzian derivative that is bounded or of slow growth. A harmonic mapping is shown to be uniformly locally univalent with respect to the hyperbolic
Chuaqui, Martin+2 more
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