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Subordinations for Functions with Positive Real Part

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Abstract

Some sufficient conditions are determined for certain first order differential subordinations to imply the corresponding analytic solution is subordinate to a rational, exponential, or sine function. By applying these results, we also obtain sufficient conditions for normalized analytic functions to be in certain well known subclasses of starlike functions.

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Correspondence to Sushil Kumar.

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Communicated by Dmitry Kaliuzhnyi-Verbovetskyi.

The authors are thankful to the referees for their comments.

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Kumar, S., Ravichandran, V. Subordinations for Functions with Positive Real Part. Complex Anal. Oper. Theory 12, 1179–1191 (2018). https://doi.org/10.1007/s11785-017-0690-4

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