Geometric Properties of Starlikeness Involving Hyperbolic Cosine Function

Abstract

In this paper, we investigate some geometric properties of starlikeness connected with the hyperbolic cosine functions defined in the open unit disk. In particular, for the class of such starlike hyperbolic cosine functions, we determine the lower bounds of partial sums, BriotBouquet differential subordination associated with Bernardi integral operator, and bounds on some third Hankel determinants containing initial coefficients.