On a class of analytic functions closely related to a class defined by Silverman and Silvia

  • S. Kavitha SDNB Vaishnav College for Women, Chennai Tamil Nadu, India
  • M. Darus Univ. Kebangsaan Malaysia, Selangor, Malaysia
  • S. Sivasubramanian Univ. College of Engineering, Anna Univ., Tindivanam, India
Keywords: Univalent; Starlike functions of order $\alpha$; Starlike function with respect to a boundary point; Coefficient estimates.

Abstract

UDC 517.5

We define and study a class of analytic functions in the unit disc by using the modification of the well-known Silverman and Silvia's analytic formula for starlike functions with respect to a boundary point. The representation theorem, as well as growth and distortion theorems are established for the new class of functions.  Further, early coefficients of the new class of functions are also estimated.

References

A. S. Abdullah, R. M. Ali, V. Singh, On functions starlike with respect to a boundary point, Ann. Univ. Mariae Curie-Skłodowska, Sect. A, 50, 7–15 (1996).}

D. Aharonov, M. Elin, D. Shoikhet, Spiral-like functions with respect to a boundary point, J. Math. Anal. and Appl., 280, No. 1, 17– 29 (2003). DOI: https://doi.org/10.1016/S0022-247X(02)00615-7

M. P. Chen, S. Owa, Generalization of Robertson functions, Complex Analysis and its Applications (Hong Kong, 1993), Pitman Res. Notes Math. Ser., 305, Longman Sci. Tech. Harlow (1994), p.~159–165.

J. Dong, L. Liu, Distortion properties of a class of functions starlike with respect of a boundary point, Heilongjiang Daxue Ziran Kexue Xuebao, 15, No. 4, 1–6 (1998).

M. Elin, S. Reich, D. Shoikhet, Dynamics of inequalities in geometric function theory, J. Inequal. and Appl., 6, No. 6, 651– 664 (2001). DOI: https://doi.org/10.1155/S1025583401000406

M. Elin, Covering and distortion theorems for spirallike functions with respect to a boundary point, Int. J. Pure and Appl. Math., 28, No. 3, 387–400 (2006).

M. Elin, D. Shoikhet, Angle distortion theorems for starlike and spirallike functions with respect to a boundary point, Intern. J. Math. and Math. Sci., 2006, Article ID 81615 (2006). DOI: https://doi.org/10.1155/IJMMS/2006/81615

M. Elin, D. Shoikhet, Linearization models for complex dynamical systems, topics in univalent functions, functions equations and semigroup theory, Birkhäuser, Basel (2010). DOI: https://doi.org/10.1007/978-3-0346-0509-0

Z. J. Jakubowski, On properties of the Pick function and some applications of them, Acta Univ. Purkyn., 42, 51–62 (1999).

Z. J. Jakubowski, A. Włodarczyk, On some classes of functions of Robertson type, Ann. Univ. Mariae Curie-Skłodowska., Sect. A, 59, 27–42 (2005).

W. Kaplan, Close-to-convex schlicht functions, Michigan Math. J., 1, 169–185 (1953). DOI: https://doi.org/10.1307/mmj/1028988895

A. Lecko, On the class of functions starlike with respect to a boundary point, J. Math. Anal. and Appl., 261, No. 2, 649–664 (2001). DOI: https://doi.org/10.1006/jmaa.2001.7564

A. Lecko, A. Lyzzaik, A note on univalent functions starlike with respect to a boundary point, J. Math. Anal. and Appl., 282, No. 2, 846–851 (2003). DOI: https://doi.org/10.1016/S0022-247X(03)00258-0

A. Lyzzaik, On a conjecture of M. S. Robertson, Proc. Amer. Math. Soc., 91, No. 1, 108–110 (1984). DOI: https://doi.org/10.1090/S0002-9939-1984-0735575-7

M. Obradović, S. Owa, On some classes of close-to-convex functions and its applications, Bull. Inst. Math. Acad. Sin., 16, No. 2, 123–133 (1988).

M. I. S. Robertson, On the theory of univalent functions, Ann. Math. (2), 37, No. 2, 374–408 (1936). DOI: https://doi.org/10.2307/1968451

M. S. Robertson, Univalent functions starlike with respect to a boundary point, J. Math. Anal. and Appl., 81, No. 2, 327– 345 (1981). DOI: https://doi.org/10.1016/0022-247X(81)90067-6

St. Ruscheweyh, T. Sheil-Small, Hadamard products of Schlicht functions and the Pólya–Schoenberg conjecture, Comment. Math. Helv., 48, 119–135 (1973). DOI: https://doi.org/10.1007/BF02566116

H. Silverman, E. M. Silvia, Subclasses of univalent functions starlike with respect to a boundary point, Houston J. Math., 16, No. 2, 289–299 (1990).

S. Sivasubramanian, On a closely related class involving spirallike functions with respect to a boundary point, Mediterr. J. Math., 17, No. 3, Article 92 (2020). DOI: https://doi.org/10.1007/s00009-020-01529-z

D. Styer, On weakly starlike multivalent functions, J. Anal. Math., 26, 217– 233 (1973). DOI: https://doi.org/10.1007/BF02790430

P. G. Todorov, On the univalent functions starlike with respect to a boundary point, Proc. Amer. Math. Soc., 97, No. 4, 602– 604 (1986). DOI: https://doi.org/10.1090/S0002-9939-1986-0845972-9

Published
26.12.2022
How to Cite
Kavitha, S., M. Darus, and S. Sivasubramanian. “On a Class of Analytic Functions Closely Related to a Class Defined by Silverman and Silvia”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 74, no. 11, Dec. 2022, pp. 1533 -43, doi:10.37863/umzh.v74i11.6523.
Section
Research articles