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

Document Type : Research Paper


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

2 Department of Mathematics, Urmia University, Urmia, Iran


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


Main Subjects

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