APPLICATIONS OF CERTAIN FUNCTIONS ASSOCIATED WITH LEMNISCATE BERNOULLI

被引:10
作者
Halim, Suzeini [1 ]
Omar, Rashidah [1 ,2 ]
机构
[1] Univ Malaya, Fac Sci, Inst Math Sci, Kuala Lumpur, Malaysia
[2] MARA Univ Technol Malaysia, Fac Comp & Math Sci, Shah Alam, Malaysia
关键词
Convex functions; differential subordination; lemniscate Bernoulli;
D O I
10.22342/jims.18.2.115.93-99
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
For J(alpha, f(z)) = (1 - alpha) zf'(z)/f(z) + alpha[1 + zf''(z)/f'(z)] (alpha >= 0), denote SL(alpha) and SLc as classes of alpha-convex and convex function which respectively satisy condition vertical bar[J(alpha, f(z))](2) - 1 vertical bar < 1 and vertical bar[1 + zf''(z)/f'(z)](2) - 1 vertical bar < 1. Using established results, namely 1 + beta zp'(z) < 1+ Dz/1+ Ez , 1 + beta zp'(z)/p(z) < 1+ Dz/1+ Ez and 1 + 1 + beta zp'(z)/p(2)(z) < 1+ Dz/1+ Ez imply p (z) < root 1+z where p(z) is an analytic function defined on the open unit disk D with p(0) = 1. This article obtains conditions so that analytic functions f belong to the classes SL(alpha) and SLc.
引用
收藏
页码:93 / 99
页数:7
相关论文
共 9 条
  • [1] DIFFERENTIAL SUBORDINATION FOR FUNCTIONS ASSOCIATED WITH THE LEMNISCATE OF BERNOULLI
    Ali, Rosihan M.
    Cho, Nak Eun
    Ravichandran, V.
    Kumar, S. Sivaprasad
    [J]. TAIWANESE JOURNAL OF MATHEMATICS, 2012, 16 (03): : 1017 - 1026
  • [2] Janowski W., 1973, ANN POL MATH, V28, P297, DOI [10.4064/ap-28-3-297-326, DOI 10.4064/AP-28-3-297-326]
  • [3] Miller S. S., 2000, MONOGRAPHS TXB PURE, V225
  • [4] Omar R., DIFFERENTIAL SUBORDI
  • [5] On sufficient condition to be in a certain subclass of starlike functions defined by subordination
    Sakol, Janusz
    [J]. APPLIED MATHEMATICS AND COMPUTATION, 2007, 190 (01) : 237 - 241
  • [6] Sokol J., 2008, J MATH APPL, V30, P46
  • [7] Sokol J., 1996, FOLIA SCI U TECH RES, V19, P101
  • [8] Coefficient Estimates in a Class of Strongly Starlike Functions
    Sokol, Janusz
    [J]. KYUNGPOOK MATHEMATICAL JOURNAL, 2009, 49 (02): : 349 - 353
  • [9] Radius problems in the class S L*
    Sokol, Janusz
    [J]. APPLIED MATHEMATICS AND COMPUTATION, 2009, 214 (02) : 569 - 573