Abstract
Making use of Ruscheweyh q-differential operator, we define a new subclass of uniformly convex functions and corresponding subclass of starlike functions with negative coefficients. The main object of this paper is to obtain, coefficient estimates, closure theorems and extreme point for the functions belonging to this new class. The results are generalized to families with fixed finitely many coefficients.
(Communicated by Stanisława Kanas)
Acknowledgement
The authors would like to thank the Editor and referees for their valuable comments which helped to improve the manuscript. The 4th author is supported by UKM grant: GUP-2017-064.
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