Meromorphic functions with missing coefficients defined by $q$-derivative

Document Type : Research Paper

Authors

1 Department of Mathematics, Payame Noor University, P. O. Box 19395-3697, Tehran, Iran

2 Department of Mathematics, Urmia University, Urmia, Iran

Abstract

By considering a fixed point in the punctured unit disk and using the $q$--derivative, a new subfamily of meromorphic and univalent functions is defined. Also, the first and second order {$q$--derivative} of meromorphic functions are introduced. Coefficient bounds, extreme points, radii of starlikeness and convexity are obtained. Furthermore, the convexity and preserving under convolution with some restrictions on parameters are investigated

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Main Subjects


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