A certain subclass of meromorphically q-starlike functions associated with the Janowski functions

Journal of Inequalities and Applications

H. M. Srivastava¹  Bilal Khan²  Nazar Khan²  Muhammad Tahir²  Qazi Zahoor Ahmad²  Shahid Mahmood³ 

[1] Department of Mathematics and Statistics, University of Victoria;Department of Mathematics, Abbottabad University of Science and Technology;Department of Mechanical Engineering, Sarhad University of Science and IT;

关键词: Meromorphically starlike functions;    Janowski functions;    q-derivative (or q-difference);    Distortion theorems;    Partial sums;    Radius of q-starlikeness;   

DOI  :  10.1186/s13660-019-2020-z

来源: DOAJ

【 摘 要 】

Abstract In this paper, the authors introduce a new subclass of meromorphic q-starlike functions which are associated with the Janowski functions. A characterization of meromorphically q-starlike functions associated with the Janowski functions has been obtained when the coefficients in their Laurent series expansion about the origin are all positive. This leads to a study of coefficient estimates, distortion theorems, partial sums, and the radius of starlikeness estimates for this class. It is seen that the class considered demonstrates, in some respects, properties analogous to those possessed by the corresponding class of univalent analytic functions with negative coefficients.

【 授权许可】

Unknown