On Some Subclasses of Strongly Starlike Analytic Functions

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El Moctar Ould Beiba


The aim of the present article is to investigate a family of univalent analytic functions on the unit disc $D$ defined for $M \geq 1$ by

$$\Re (\frac{zf'(z)}{f(z)}) > 0, |(\frac{zf'(z)}{f(z)})^2 - M|<M, z \in D.$$

Some proprieties, radius of convexity and coefficient bounds are obtained for classes in this family.

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