IJAM: Volume 37, No. 6 (2024)

JANOWSKI SUBORDINATION AND RADIUS PROBLEMS

FOR A LIBERA-BERNARDI TYPE INTEGRAL OPERATOR

Rajender Tak

Electronics Department of Govt. Women Polytechnic College, Bikaner

Abstract. This paper studies a LiberaвЂ“Bernardi type integral operator in connection with Janowski starlike and Janowski convex functions. Subordination criteria are obtained from an elementary differential identity, and the operator is shown to preserve several geometric subclasses under natural restrictions on its parameter. Coefficient estimates, growth bounds and radii of starlikeness and convexity are also derived. The results are formulated for the Janowski function (1+Az)/(1+Bz), and hence include the usual classes of order alpha as special cases.

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How to cite this paper?
Source: International Journal of Applied Mathematics
ISSN printed version: 1311-1728
ISSN on-line version: 1314-8060
Year: 2024
Volume: 37
Issue: 6

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