SECOND HANKEL DETERMINANT FOR CERTAIN SUBCLASSES OF BI-STARLIKE FUNCTIONS DEFINED BY DIFFERENTIAL OPERATORS

Orhan H., Arıkan H., Çağlar M.

SAHAND COMMUNICATIONS IN MATHEMATICAL ANALYSIS, cilt.20, sa.2, ss.65-83, 2023 (ESCI) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 20 Sayı: 2
  • Basım Tarihi: 2023
  • Doi Numarası: 10.22130/scma.2022.553738.1110
  • Dergi Adı: SAHAND COMMUNICATIONS IN MATHEMATICAL ANALYSIS
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), Scopus, zbMATH, Directory of Open Access Journals
  • Sayfa Sayıları: ss.65-83
  • Anahtar Kelimeler: Analytic functions, Univalent functions, Bi-univalent func-tions, Bi-starlike functions, Subordination between analytic functions, Hankel deter-minant, COEFFICIENT BOUNDS, UNIVALENT FUNCTIONS, GENERAL SUBCLASS
  • Atatürk Üniversitesi Adresli: Evet

Özet

In this paper, we obtain upper bounds of the initial Taylor-Maclaurin coefficients |a2|, |a3| and |a4| and of the Fekete-Szego functional vertical bar a3 - eta a(2) (2)vertical bar for certain subclasses of analytic and 2 bi-starlike functions S sigma*(beta,theta, n, m) in the open unit disk. We have also obtained an upper bound of the functional vertical bar a(2)a(4) - a(2) vertical bar for the 3 functions in the class S sigma*(beta,theta, n, m). Moreover, several interesting applications of the results presented here are also discussed.