Coefficient inequalities for starlikeness and convexity

Main Article Content

Ali Rosihan M.
Mahnaz M. Nargesi
Ravichandran V.

Abstract

For an analytic function $f(z)=z+\sum_{n=2}^\infty a_n z^n$ satisfying the inequality $\sum_{n=2}^\infty n(n-1)|a_n|\leq \beta$, sharp bound on $\beta$ is determined so that $f$ is either starlike or convex of order $\alpha$. Several other coefficient inequalities related to certain subclasses are also investigated.

Article Details

How to Cite
Rosihan M., A., M. Nargesi, M., & V., R. (2012). Coefficient inequalities for starlikeness and convexity. Tamkang Journal of Mathematics, 44(2), 149–162. https://doi.org/10.5556/j.tkjm.44.2013.1041
Section
Papers
Author Biography

Ravichandran V., Department ofMathematics, University of Delhi, Delhi 110 007, India; School ofMathematical Sciences, Universiti SainsMalaysia, 11800 USM, Penang,Malaysia.

Visiting Professor, School of Mathematical Sciences, USM

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