On Certain Novel Subclasses of Analytic and Univalent Functions

  • Irmak, Huseyin (Department of Mathematics Education, Faculty of Education, Baskent University) ;
  • Joshi, Santosh Bhaurao (Department of Mathematics, Walchand College of Engineering) ;
  • Raina, Ravinder Krishen (Department of Mathematics, College of Technology and Engineering, M. P. University of Agriculture and Technology)
  • Received : 2005.07.18
  • Published : 2006.12.23

Abstract

The purpose of the present paper is to introduce two novel subclasses $\mathcal{T}_{\mu}(n,{\lambda},{\alpha})$ and $\mathcal{H}_{\mu}(n,{\lambda},{\alpha};{\kappa})$ of analytic and univalent functions with negative coefficients, involving Ruscheweyh derivative operator. The various results investigated in this paper include coefficient estimates, distortion inequalities, radii of close-to-convexity, starlikenes, and convexity for the functions belonging to the class $\mathcal{T}_{\mu}(n,{\lambda},{\alpha})$. These results are then appropriately applied to derive similar geometrical properties for the other class $\mathcal{H}_{\mu}(n,{\lambda},{\alpha};{\kappa})$ of analytic and univalent functions. Relevant connections of these results with those in several earlier investigations are briefly indicated.

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References

  1. O. Altınta¸s, On a subclass of certain starlike functions with negative coefficients, Math. Japon., 36(3)(1991), 489-495.
  2. O. Altıntas, O. Ozkan and H. M. Srivastava, Neighborhoods of a certain family of multivalent functions with negative coefficients, Comput. Math. Appl., 47(2004), 1167- 1672.
  3. M. P. Chen, H. Irmak, H. M. Srivastava, A certain subclass of analytic functions involving operators of fractional calculus, Comput. Math. Appl., 35(5)(1998), 83-91.
  4. H. Irmak and R. K. Raina, Some applications of generalized fractional calculus operator to a novel class of analytic functions with negative coefficients, Taiwanese J. Math., 8(3)(2004), 443-452. https://doi.org/10.11650/twjm/1500407664
  5. G. Murugusundaramoorthy and H. M. Srivastava, Neighborhoods of certain classes of analytic functions of complex order, J. Inequal. Pure Appl. Math., 5(2), Art. No. 24(2004), 1-8.
  6. R. K. Raina and H. M. Srivastava, Some subclasses of analytic functions associated with fractional calculus operators, Comput. Math. Appl., 37(9)(1999), 73-84.
  7. St. Ruscheweyh, New criteria for univalent functions, Proc. Amer. Math. Soc., 49(1975), 109-115. https://doi.org/10.1090/S0002-9939-1975-0367176-1
  8. H. M. Srivastava and S. Owa (Editors), Current Topics in Analytic Function Theory, World Scientific, Singapore, 1992.