Results 21 to 30 of about 59 (59)
A new criterion for starlike functions
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 3, Page 613-614, 1996., 1995 In this paper we shall get a new criterion for starlikeness, and the hypothesis of this criterion is much weaker than those in [1] and [2].
Ling Yi, Shusen Ding
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Univalent functions maximizing Re[f(ζ1) + f(ζ2)]
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 4, Page 789-795, 1996., 1995 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 or z1, z2 are both real, and are in a neighborhood of the x‐axis.
Intisar Qumsiyeh Hibschweiler
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Convex functions and the rolling circle criterion
International Journal of Mathematics and Mathematical Sciences, Volume 18, Issue 4, Page 799-811, 1995., 1993 Given 0 ≤ R1 ≤ R2 ≤ ∞, CVG(R1, R2) denotes the class of normalized convex functions f in the unit disc U, for which ∂f(U) satisfies a Blaschke Rolling Circles Criterion with radii R1 and R2. Necessary and sufficient conditions for R1 = R2, growth and distortion theorems for CVG(R1, R2) and rotation theorem for the class of convex functions of bounded ...
V. Srinivas, O. P. Juneja, G. P. Kapoor
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Quasiconformal harmonic mappings and close-to-convex domains
, 2010 Let f = h + ? be a univalent sense preserving harmonic mapping of the unit disk U onto a convex domain ?. It is proved that: for every a such that |a| < 1 (resp. |a| = 1) the mapping ?a = h + a?
David Kalaj
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On polynomial expansion of multivalent functions
International Journal of Mathematics and Mathematical Sciences, Volume 14, Issue 3, Page 443-446, 1991., 1991 Coefficient bounds for mean p‐valent functions, whose expansion in an ellipse has a Jacobi polynomial series, are given in this paper.
M. M. Elhosh
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Symmetric Toeplitz Determinants for Classes Defined by Post Quantum Operators Subordinated to the Limaçon Function [PDF]
The present extensive study is focused to find estimates for the upper bounds of the Toeplitz determinants. The logarithmic coefficients of univalent functions play an important role in different estimates in the theory of univalent functions, and in ...
SANGARAMBADI PADMANABHAN, Vijayalakshmi +2 more
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Sufficient conditions for spiral‐likeness
International Journal of Mathematics and Mathematical Sciences, Volume 12, Issue 4, Page 641-644, 1989., 1989 Coefflcient conditions sufficient for splral‐likenss are found by convolution methods. The order of starlikeness for such functions is also determined.
H. Silverman
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Some classes involving a convolution of analytic functions with some univalency conditions [PDF]
In this paper, involving a convolution f ∗ g, two classes of normalized analytic functions f are defined. Showing an inclusion relation between these classes, various sufficient conditions for functions to be in these classes are established.
MISHRA, Omendra +3 more
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On Subclasses of Spiral‐Like Functions Defined by the q‐Derivative Operator
Journal of Function Spaces, Volume 2026, Issue 1, 2026.In 1990, Ismail et al. introduced a generalized class of starlike functions using the q‐derivative operator. Similarly, many authors have studied various subclasses of analytic functions involving the q‐derivative operator from different perspectives. This paper is aimed at presenting new subclasses of analytic and spiral‐like functions related to the ...
Fatma Z. El-Emam +2 more
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Some classes of alpha‐quasi‐convex functions
International Journal of Mathematics and Mathematical Sciences, Volume 11, Issue 3, Page 497-501, 1988., 1986 Let C[C, D], −1 ≤ D < C ≤ 1 denote the class of functions g, g(0) = 0, g′(0) = 1, analytic in the unit disk E such that is subordinate to , z ∈ E. We investigate some classes of Alpha‐Quasi‐Convex Functions f, with f(0) = f′(0) − 1 = 0 for which there exists a g ∈ C[C, D] such that is subordinate to , −1 ≤ B < A ≤ 1.
Khalida Inayat Noor
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