Results 11 to 20 of about 275 (34)
Extreme points and convolution properties of some classes of multivalent functions
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 2, Page 381-388, 1996., 1991 This paper deals with the extreme points of closed convex hulls of the classes of multivalent functions related to Ruscheweyh derivatives and then these are used to determine the coefficient bounds. Finally, we investigate convolution conditions and other properties of the functions in these classes.
O. P. Ahuja
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Close‐to‐starlike logharmonic mappings
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 3, Page 563-573, 1996., 1994 We consider logharmonic mappings of the form defined on the unit disc U which can be written as the product of a logharmonic mapping with positive real part and a univalent starlike logharmonic mapping. Such mappings will be called close‐to‐starlike logharmonic mappings. Representation theorems and distortion theorems are obtained.
Zayid Abdulhadi
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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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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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Univalence criterion for meromorphic functions and Loewner chains
, 2011 The object of the present paper is to obtain a more general condition for univalence of meromorphic functions in the U*. The significant relationships and relevance with other results are also given.
Becker +13 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 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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Subclasses of close‐to‐convex functions
International Journal of Mathematics and Mathematical Sciences, Volume 6, Issue 3, Page 449-458, 1983., 1983 Let 𝒦[C, D], −1 ≤ D < C ≤ 1, denote the class of functions g(z), g(0) = g′(0) − 1 = 0, analytic in the unit disk U = {z : |z| < 1} such that 1 + (zg″(z)/g′(z)) is subordinate to (1 + Cz)/(1 + Dz), z ϵ U. We investigate the subclasses of close‐to‐convex functions f(z), f(0) = f′(0) − 1 = 0, for which there exists g ϵ 𝒦[C, D] such that f′/g′ is ...
E. M. Silvia
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