Bulletin of the Korean Mathematical Society (대한수학회보)

Korean Mathematical Society (대한수학회)
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PARTIAL SUMS AND INCLUSION RELATIONS FOR STARLIKE FUNCTIONS ASSOCIATED WITH AN EVOLUTE OF A NEPHROID CURVE

  • Gurpreet Kaur (Department of Mathematics Mata Sundri College for Women University of Delhi) ;
  • Sumit Nagpal (Department of Mathematics University of Delhi)
  • Received : 2022.08.23
  • Accepted : 2022.09.06
  • Published : 2023.11.30
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Abstract

A class of normalized univalent functions f defined in an open unit disk of the complex plane is introduced and studied such that the values of the quantity zf'(z)/f(z) lies inside the evolute of a nephroid curve. The inclusion relations of the newly defined class with other subclasses of starlike functions and radius problems concerning the second partial sums are investigated. All the obtained results are sharp.

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References

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