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On a Subclass of Strongly Starlike Functions Associated with Exponential Function

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Abstract

Let \(\fancyscript{S}_{e}^*\) denote the class of analytic functions \(f\) in the open unit disk normalized by \(f(0)=f'(0)-1=0\) and satisfying the condition \(zf'(z)/f(z)\prec e^z\) for \(|z|<1\). The structural formula, inclusion relations, coefficient estimates, growth and distortion results, subordination theorems and various radii constants for functions in the class \(\fancyscript{S}_{e}^*\) are obtained. In addition, the sharp \(\fancyscript{S}_{e}^*\)-radii for functions belonging to several interesting classes are also determined.

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Acknowledgments

The work presented here was supported in parts by a Senior Research Fellowship from CSIR, New Delhi, and also by a grant from University of Delhi.

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Authors and Affiliations

  1. Department of Mathematics, University of Delhi, Delhi, 110007, India

    Rajni Mendiratta, Sumit Nagpal & V. Ravichandran

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  1. Rajni Mendiratta
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  2. Sumit Nagpal
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  3. V. Ravichandran
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Correspondence to Sumit Nagpal.

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Communicated by Lee See Keong.

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Mendiratta, R., Nagpal, S. & Ravichandran, V. On a Subclass of Strongly Starlike Functions Associated with Exponential Function. Bull. Malays. Math. Sci. Soc. 38, 365–386 (2015). https://doi.org/10.1007/s40840-014-0026-8

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  • DOI: https://doi.org/10.1007/s40840-014-0026-8

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