Limits: Journal of Mathematics and Its Applications
Vol 3, No 1 (2006)

On Subclass of Bazilevi·c Function B1(®), It's Distortion and the Fekete-SzegÄo Problem

Marjono Marjono (Unknown)



Article Info

Publish Date
24 May 2006

Abstract

In this paper we present the distortion and the Fekete-SzegÄo problem of subclass of Bazilevi·c functions, B1(®). First, we present the result of Singh concerning the sharp value of the coe±cients for B1(®), ja2j, ja3j and ja4j. Second, we give a solution of the Fekete-SzegÄo problem, i.e. an estimateof ja3 ¡ ¹a 2 2j for any real and complex numbers ¹ where a2 and a3 are the coe±cients of functions f in B1(®), where B1(®) is de¯ned by (2), i.e. for each ® > 0 and for z 2 D, Re f 0 (z) f(z)z ®¡1 > 0. These results are sharp for the functions f0 de¯ned by (3) for any real number ¹ which satis¯es ¹ < (1 ¡ ®)=2, or ¹ ¸ (4 + 3® + ® )=[2(2 + ®)] and for any complex number ¹ which satis¯es j3 + ® ¡ 2¹(2 + ®)j ¸ (1 + ®) 2 . These results are sharp for the functions f1 de¯ned by (4) for the other real and complex numbers ¹. Next, we use similar methods to get estimates for linear expressions involving higher coe±cients of function in B1(®). 2

Copyrights © 2006






Journal Info

Abbrev

limits

Publisher

Subject

Mathematics

Description

Limits: Journal of Mathematics and Its Applications merupakan jurnal yang diterbitkan oleh Lembaga Penelitian dan Pengabdian Kepada Masyarakat (LPPM) Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia. Limits menerima makalah hasil riset di semua bidang Matematika, terutama bidang Analisis, ...