Coefficient bounds and Fekete-Szeg¨o inequality for a unified subclass of m-fold symmetric bi-univalent functions

Navyodh Singh; Gagandeep Singh; Navjeet Singh

doi:10.24193/subbmath.2026.2.05

Authors

Navyodh Singh Department of Mathematics, Khalsa College, Amritsar-143001, Punjab, India https://orcid.org/0000-0003-0611-2508
Gagandeep Singh Department of Mathematics, Khalsa College, Amritsar-143001, Punjab, India https://orcid.org/0000-0001-5238-3603
Navjeet Singh Department of Mathematics, Khalsa College, Amritsar-143001, Punjab, India https://orcid.org/0000-0001-7440-8373

DOI:

https://doi.org/10.24193/subbmath.2026.2.05

Keywords:

Analytic functions, Fekete-Szego, Subordination, Coef f icient inequality

Abstract

In this paper, we introduce a new and unified subclass of m-fold symmetric biunivalent functions by subordinating to generalized Janowski function, in the open unit disc E = {z :| z |< 1}. Bounds for the initial coefficients and Fekete-Szeg¨o inequality for the functions in this class are studied. Particular cases of the results derived here are also discussed.

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