Certain subclass of close-to-convex univalent functions defined with q-derivative operator

Gagandeep Singh; Gurcharanjit Singh

doi:10.24193/subbmath.2025.3.05

Authors

Gagandeep Singh Department of Mathematics, Khalsa College, Amritsar, Punjab, India https://orcid.org/0000-0001-5238-3603
Gurcharanjit Singh Department of Mathematics, G.N.D.U. College, Chungh, Punjab, India https://orcid.org/0000-0002-8484-7545

DOI:

https://doi.org/10.24193/subbmath.2025.3.05

Keywords:

Analytic functions, Univalent functions, Close-to-convex functions, Coefficient bounds, qderivative, Subordination, Hypergeometric function, Hadamard product.

Abstract

The objective of this paper is to introduce a new subclass of strongly close-to-convex functions defined with q-derivative operator and by subordinating to generalized Janowski function. We establish several useful properties such as coefficient estimates, distortion theorem, argument theorem, inclusion relations and radius of convexity for this class. Some relevant connections of the results investigated here with those derived earlier are mentioned.

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