# A COEFFICIENT INEQUALITY FOR CERTAIN CLASSES OF ANALYTIC FUNCTIONS

## Main Article Content

## Abstract

Let

\[ f(z)=z+\sum_{k=2}^\infty c_kz^k \]

be analytic in the unit disc $E=\{z:|z|<1\}$. We wish to maximize $|a_3- ua_2^2|$ over certain classes of analytic functions defined by convex subordination. This paper is concerned with the solution of the above extremal problem over certain classes of univalent analytic functions.

## Article Details

*Tamkang Journal of Mathematics*,

*22*(2), 153–163. https://doi.org/10.5556/j.tkjm.22.1991.4588

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