Abstract
Let \(S_{\cos }^{*}\) denote the class of normalized analytic functions f such that \(\frac{zf^{\prime }(z)}{f(z)}\prec \cos (z)\). For this class, we obtain structural formula, inclusion results, differential subordinations and some radii problems such as radius of convexity, radius for the class of Janowski starlike functions and radius for some other subclasses of starlike functions.
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Communicated by Hamid Reza Ebrahimi Vishki.
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Bano, K., Raza, M. Starlike Functions Associated with Cosine Functions. Bull. Iran. Math. Soc. 47, 1513–1532 (2021). https://doi.org/10.1007/s41980-020-00456-9
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DOI: https://doi.org/10.1007/s41980-020-00456-9