Radii of starlikeness and convexity of Bessel function derivatives

Abstract

UDC 517.5 In this paper, our aim is to find the radii of starlikeness andconvexity of Bessel function derivatives for three different kind of normalization. The key tools in the proof of our main results are the Mittag-Leffler expansion for th derivative of Bessel function andproperties of real zeros of it. In addition, by using the Euler–Rayleigh inequalities we obtain some tight lower and upper bounds for the radii of starlikeness and convexity of order zero for the normalized th derivative of Bessel function. The main results of the paper are natural extensions of some known results on classical Bessel functions of the first kind.