Coefficient Estimates for Subclasses of Bi-Univalent Functions

Abstract

In the present paper, we introduce two new subclasses of the class consisting of analytic and bi-univalent functions in the open unit disk . Also, we obtain the estimates on the Taylor-Maclurin coefficients and for functions in these subclasses. We obtain new special cases for our results.

Results on Fourth Hankel Determinant of a Certain Subclass of Analytic Functions

“…2 is the wellknown Fekete-Szegő functional. The second Hankel determinant 𝐻 2 (2) defined as 𝐻 2 (2) = 𝑎 2 𝑎 4 − 𝑎 3 2 was studied for the classes of bi-starlike and bi-convex functions [1,6,7,8,9,11,19,20,21] ,also see( [2,4,5,6,7,14,15,16,17,18]. For the third Hankel determinant is given as…”