Bounds for radii of starlikeness and convexity of some special functions

ORHAN, Halit; BARICZ, Arpad; Aktaş, İbrahim

Bounds for radii of starlikeness and convexity of some special functions

İbrahim AKTAŞ, (Gümüşhane Üniversitesi, Matematik Mühendisliği Bölümü, Gümüşhane, Türkiye)

Arpad BARICZ, (Department of Economics, Babes-Bolyai University, Cluj-Napoca, Romania)

Halit ORHAN (Atatürk Üniversitesi, Fen Fakültesi, Matematik Bölümü, Erzurum, Türkiye)

Turkish Journal of Mathematics

1 0

Yıl: 2018 Cilt: 42 Sayı: 1 Sayfa Aralığı: 211 - 226 Metin Dili: İngilizce İndeks Tarihi: 29-07-2022

Bounds for radii of starlikeness and convexity of some special functions

Öz:

In this paper we consider some normalized Bessel, Struve, and Lommel functions of the rst kind and, byusing the Euler{Rayleigh inequalities for the rst positive zeros of a combination of special functions, we obtain tightlower and upper bounds for the radii of starlikeness of these functions. By considering two different normalizations ofBessel and Struve functions we give some inequalities for the radii of convexity of the same functions. On the otherhand, we show that the radii of univalence of some normalized Struve and Lommel functions are exactly the radii ofstarlikeness of the same functions. In addition, by using some ideas of Ismail and Muldoon we present some new lowerand upper bounds for the zeros of derivatives of some normalized Struve and Lommel functions. The Laguerre{P olyaclass of real entire functions plays an important role in our study.

Anahtar Kelime:

Konular: Matematik

Belge Türü: Makale Makale Türü: Araştırma Makalesi Erişim Türü: Erişime Açık

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APA	Aktaş İ, BARICZ A, ORHAN H (2018). Bounds for radii of starlikeness and convexity of some special functions. , 211 - 226.
Chicago	Aktaş İbrahim,BARICZ Arpad,ORHAN Halit Bounds for radii of starlikeness and convexity of some special functions. (2018): 211 - 226.
MLA	Aktaş İbrahim,BARICZ Arpad,ORHAN Halit Bounds for radii of starlikeness and convexity of some special functions. , 2018, ss.211 - 226.
AMA	Aktaş İ,BARICZ A,ORHAN H Bounds for radii of starlikeness and convexity of some special functions. . 2018; 211 - 226.
Vancouver	Aktaş İ,BARICZ A,ORHAN H Bounds for radii of starlikeness and convexity of some special functions. . 2018; 211 - 226.
IEEE	Aktaş İ,BARICZ A,ORHAN H "Bounds for radii of starlikeness and convexity of some special functions." , ss.211 - 226, 2018.
ISNAD	Aktaş, İbrahim vd. "Bounds for radii of starlikeness and convexity of some special functions". (2018), 211-226.

APA	Aktaş İ, BARICZ A, ORHAN H (2018). Bounds for radii of starlikeness and convexity of some special functions. Turkish Journal of Mathematics, 42(1), 211 - 226.
Chicago	Aktaş İbrahim,BARICZ Arpad,ORHAN Halit Bounds for radii of starlikeness and convexity of some special functions. Turkish Journal of Mathematics 42, no.1 (2018): 211 - 226.
MLA	Aktaş İbrahim,BARICZ Arpad,ORHAN Halit Bounds for radii of starlikeness and convexity of some special functions. Turkish Journal of Mathematics, vol.42, no.1, 2018, ss.211 - 226.
AMA	Aktaş İ,BARICZ A,ORHAN H Bounds for radii of starlikeness and convexity of some special functions. Turkish Journal of Mathematics. 2018; 42(1): 211 - 226.
Vancouver	Aktaş İ,BARICZ A,ORHAN H Bounds for radii of starlikeness and convexity of some special functions. Turkish Journal of Mathematics. 2018; 42(1): 211 - 226.
IEEE	Aktaş İ,BARICZ A,ORHAN H "Bounds for radii of starlikeness and convexity of some special functions." Turkish Journal of Mathematics, 42, ss.211 - 226, 2018.
ISNAD	Aktaş, İbrahim vd. "Bounds for radii of starlikeness and convexity of some special functions". Turkish Journal of Mathematics 42/1 (2018), 211-226.