Fixed coefficients for certain subclasses of starlike functions with negative coefficients

• Autorzy: Aouf M. , Al-Dohiman A.
• Języki publikacji: EN

Abstrakty

EN

The main object of this paper is to study the class T*n,c(alfa,beta) of analytic functions with negative coefficients and with fixed second coefficients. Among other results of interest, we derive coefficient estimates, closure properties involving convex linear combinations, growth and distortion theorems, and radii of starlikeness and convexity for functions in the class T*n,c(alfa,beta). Many of these results are further extended to hold true for families of functions with finitely many fixed coefficients.

Słowa kluczowe

EN

analytic functions; starlike functions; Ruschewyh derivative; certain subclasses; negative coefficients

PL

funkcje analityczne; funkcje gwiaździste; pochodne Ruscheweyha; podklasy pewne; współczynniki ujemne

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2005
• Tom: Vol. 38, nr 3
• Strony: 551--565
• Opis fizyczny: Bibliogr. 8 poz.

Twórcy

autor

Aouf M.

• Mathematics Department, Girls College of Education Sciences Sections, Jeddah, Saudi Arabia

autor

Al-Dohiman A.

• P.O.Box 762 Al-Jouf, Saudi Arabia

Bibliografia

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• [2] V. P. Gupta and P. K. Jain, Certain classes of univalent functions with negative coefficients, Bull. Austral. Math. Soc. 14 (1976), 409-416.
• [3] H. M. Hossen, Generalization of certain classes of univalent functions with negative coefficient, Studia Univ. (Babes-Bolyai), Math. 2 (2001), 41-58.
• [4] J. Patel and M. Acharya, Certain subclasses of starlike functions with negative coefficients, Bull. Cal. Math. Soc. 87 (1995), 265-276.
• [5] St. Ruscheweyh, New criteria for univalent functions, Proc. Amer. Math. Soc. 49 (1975), 109-115.
• [6] H. Silverman, Univalent functions with negative coefficients, Proc. Amer. Math. Soc. 51 (1975), 109-116.
• [7] H. Silverman and E. M. Silvia., Fixed coefficients for subclasses of starlike functions, Houston J. Math. 7 (1981), no. 1, 129-136.
• [8] B. A. Uralegaddi and M. D. Ganigi, Fixed coefficients for certain univalent functions with negative coefficients, Mathematics Today 4 (1986), 25-32.