On Certain New Subclass of Sakaguchi Type Function Related to Sigmoid Functions
About this article
DOI:
https://doi.org/10.14419/ijet.v7i4.36.24238Keywords:
coefficient estimate, Analytic function, univalent function, Starlike function, convex functionsubordination, upper bound, sigmoid function, differential operator, second Hankel determinant.Abstract
The object of the present paper is to obtain initial coefficients | |,| |,| |, upper bounds of | | and second Hankel determinant associated with a class of analytic univalent function of sakaguchi type function related to sigmoid function in the open unit disc ∆. Various authors as Abiodum, Tinuoye Oladipo, Murugusundaramoorthy et. al., and Olatunji have studied sigmoid function for different classes of analytic and univalent functions. Our results serves as a generalisation in this direction and it gives birth some existing subclasses of functions.
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