INITIAL COEFFICIENT BOUNDS FOR NEW SUBCLASSES OF <i>M</i>-FOLD SYMMETRIC BI-UNIVALENT FUNCTIONS WITH BOUNDED BOUNDARY ROTATION

Prathviraj Sharma; S. Sivasubramanian; Nak Eun Cho

doi:10.11948/20240075

2026 Volume 16 Issue 2

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Prathviraj Sharma, S. Sivasubramanian, Nak Eun Cho. INITIAL COEFFICIENT BOUNDS FOR NEW SUBCLASSES OF M-FOLD SYMMETRIC BI-UNIVALENT FUNCTIONS WITH BOUNDED BOUNDARY ROTATION[J]. Journal of Applied Analysis & Computation, 2026, 16(2): 705-723. doi: 10.11948/20240075

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Prathviraj Sharma, S. Sivasubramanian, Nak Eun Cho. INITIAL COEFFICIENT BOUNDS FOR NEW SUBCLASSES OF M-FOLD SYMMETRIC BI-UNIVALENT FUNCTIONS WITH BOUNDED BOUNDARY ROTATION[J]. Journal of Applied Analysis & Computation, 2026, 16(2): 705-723. doi: 10.11948/20240075

INITIAL COEFFICIENT BOUNDS FOR NEW SUBCLASSES OF M-FOLD SYMMETRIC BI-UNIVALENT FUNCTIONS WITH BOUNDED BOUNDARY ROTATION

1.
Department of Mathematics, University College of Engineering Tindivanam, Anna University, Tindivanam 604001, Tamilnadu, India
2.
Department of Applied Mathematics, Pukyong National University, Busan 48513, Republic of Korea

Author Bio: Email: sirprathvi99@gmail.com(P. Sharma); Email: necho@pknu.ac.kr(N. E. Cho)
Corresponding author: Email: sivasaisastha@rediffmail.com(S. Sivasubramanian)

Abstract

Abstract

In the present article, the authors introduce the concept of m-fold symmetric bi-univalent functions with bounded boundary rotation and introduce three new subclasses of m-fold symmetric bi-univalent functions. For the newly defined classes, the authors obtain first two initial coefficient bounds. Furthermore, the Fekete-Szegö bounds are also obtained for these three new classes of functions. Apart from many new results and new corollaries, the results in this article also improves earlier existing bounds available in the literature.
- Analytic /
- univalent /
- bi-univalent /
- m-fold symmetric functions /
- bounded boundary rotation /
- coefficient estimates
MSC: Primary: 30C45, 33C50; Secondary: 30C80

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References

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