A Class of Analytic Starlike Functions Associated with Petal Like Region on the Positive Half of Complex Plane
Authors
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Department of Mathematics, Govt. Post Graduate College, Gopeshwar, Chamoli Uttarakhand - 246401 ,IN
Rajesh Kumar Maurya -
Department of Mathematics and Astronomy, Lucknow University Lucknow - 222207 ,INPoonam Sharma
DOI:
https://doi.org/10.18311/jims/2020/25449Keywords:
Strongly starlike functions, petal like region, subordination, Hankel DeterminantAbstract
In the light of Riemann open mapping theorem, if we map open unit disk U conformally onto a region then depending on the geometry of boundary of we can always extract a subclass of H[a, n] by subordinating various functionals of the function f ∈ H[a, n]. Depending upon the geometry of the range set attempts have been made to find some algebraic structure in such classes, for that Hankel determinant of coefficients of functions pertaining to these classes have been studied, bounds of various coefficients have been determined and also based on the subordination principle we have determined radius |z| < r ;z ∈ U for which f belongs to such a class. In this paper our focus would be on n−PS* defined as n − PS* = {f ∈ A : Re {zf'(z)/f(z)} > 0,|(zf'(z)/f(z))n - 1|<1}.
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Copyright (c) 2020 Rajesh Kumar Maurya, Poonam Sharma
This work is licensed under a Creative Commons Attribution 4.0 International License.
Accepted 2023-01-30
Published 2020-07-01
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