Abstract
We introduce a class \({\mathfrak {R}}_{\alpha }^{q}\) of q-prestarlike functions of order \(\alpha \) by using q-difference operator. We obtain necessary and sufficient conditions involving convolution for functions to be in the class \({\mathfrak {R}}_{\alpha }^{q}.\) We prove that the well-known class of analytic prestarlike functions, \({\mathfrak {R}}_{\alpha },\) is properly contained in \({\mathfrak {R}}_{\alpha }^{q}.\) Apart from finding bounds on some initial coefficients of functions in the class \({\mathfrak {R}}_{\alpha }^{q}\), we also investigate some convolution properties of functions in the class \({\mathfrak {R}}_{\alpha }^{q}.\) The results of the present manuscript essentially generalize some well-known results in the literature.
Similar content being viewed by others
Data availability
Not applicable.
References
Ahuja, O.P., Cetinkaya, A.: Use of quantum calculus approach in mathematical sciences and its role in geometric function theory. AIP Conf. Proc. 2095, 020001 (2019)
Ahuja, O.P., Silverman, H.: Convolutions of prestarlike functions. Int. J. Math. Math. Sci. 6(1), 59–68 (1983)
Ahuja, O.P., Cetinkaya, A., Polatoglu, Y.: Bieberbach-de Branges and Fekete–Szegö inequalities for certain families of \(q\)-convex and \(q\)-close-to-convex functions. J. Comput. Anal. Appl. 26(4), 639–649 (2019)
Carlson, B.C., Shaffer, D.B.: Starlike and prestarlike hypergeometric functions. SIAM J. Math. Anal. 15(4), 737–745 (1984)
Darus, M.: A unified treatment of certain subclasses of prestarlike functions. J. Inequal. Appl. 6(5), 1–7 (2005)
Dziok, J.: Applications of multivalent prestarlike functions. Appl. Math. Comput. 221, 230–238 (2013)
Ismail, M.E.H., Merkes, E., Styer, D.: A generalization of starlike functions. Complex Variables 14, 77–84 (1990)
Jackson, F.H.: On \(q\)-functions and a certain differential operator. Trans. R. Soc. Edinburgh 46, 253–281 (1920)
Jackson, F.H.: On \(q\)-definite integrals. Q. J. Pure Appl. Math. 41, 193–203 (1990)
Keough, F., Merkes, E.: A coefficient inequality for certain classes of analytic functions. Proc. Am. Math. Soc. 20, 8–12 (1969)
Khan, B., Srivastava, H.M., Khan, N., Darus, M., Ahmad, Q.Z., Tahir, M.: Some general families of \(q\)-starlike functions associated with the Janowski functions. Filomat 33(9), 2613–2626 (2019)
Libera, R.J., Złotkiewicz, E.J.: Coefficient bounds for the inverse of a function with derivative in \({\cal{P} }\). Proc. Am. Math. Soc. 87(2), 251–257 (1983)
Piejko, K., Sokół, J.: On convolution and \(q\)-calculus. Bol. Soc. Mat. Mex. 26, 349–359 (2020)
Piejko, K., Sokół, J., Trabka-Wiecław, K.: On \(q\)-calculus and starlike functions. Iran. J. Sci. Technol. Trans. A 43, 2879–2883 (2019)
Pommerenke, C.: Univalent functions, Studia Mathematica/Mathematische Lehrbücher, vol. XXV. Vandenhoeck & Ruprecht, Göttingen (1975)
Raghavendar, K., Swaminathan, A.: Close-to-convexity of basic hypergeometric functions using their Taylor coefficients. J. Math. Appl. 35, 111–125 (2012)
Ruscheweyh, S.: Linear operators between classes of prestarlike functions. Comment. Math. Helvetici 52, 497–509 (1977)
Ruscheweyh, S., Sheil-Small, T.: Hadamard products of Schlicht fucntions and the Pólya–Schoenberg conjecture. Comment. Math. Helv. 48, 119–135 (1973)
Selvakumaran, K.A., Choi, J., Purohit, S.D.: Certain subclasses of analytic functions defined by fractional \(q\)-calculus operators. Appl. Math. E-Notes 21, 72–80 (2021)
Singh, R., Singh, S.: Convolution properties of a class of starlike functions. Proc. Am. Math. Soc. 106(1), 145–152 (1989)
Srivastava, H.M., Owa, S.: Univalent Functions, Fractional Calculus, and Associated Generalized Hypergeometric Functions, in Univalent Functions, Fractional Calculus, and Their Applications (Kōriyama. Ellis Horwood Ser. Math, Appl, pp. 329–354. Horwood, Chichester (1988)
Suffridge, T.J.: Starlike functions as limits of polynomials. In: Kirwan, W.E., Zalcman, L. (eds.) Advances in Complex Function Theory. Lecture Notes in Mathematics, vol. 505, pp. 164–203. Springer, Berlin (1976)
Uçar, H.E.O.: Coefficient inequality for \(q\)-starlike functions. Appl. Math. Comput. 276, 122–126 (2016)
Verma, S., Kumar, R., Sokół, J.: A conjecture on Marx–Strohhäcker type inclusion relation between \(q\)-convex and \(q\)-starlike functions. Bull. Sci. Math. 174, 10 (2022)
Acknowledgements
Not Applicable.
Funding
Not applicable.
Author information
Authors and Affiliations
Contributions
S.V. and R.K. developed the idea of analog class of prestarlike functions using q-derivatives and discussed it with O.P. and A.C. Further, all the authors contributed significantly to obtain main results of the present manuscript and have reviewed the manuscript carefully.
Corresponding author
Ethics declarations
Conflict of interest
The authors have no conflicts of interest to declare.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Verma, S., Kumar, R., Ahuja, O.P. et al. q-Analog of prestarlike functions. Complex Anal Synerg 10, 11 (2024). https://doi.org/10.1007/s40627-024-00137-x
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s40627-024-00137-x