In [6] it was shown that if f ∈ is starlike of order α, α= 0.294, . . . , so is the Libera integral operator F . We also know that (see, e.g., [1]) there are functions which are univalent or spiral-like in so that their Libera integral operators are not univalent or spiral-like in . Li and Owa [5] proved that if f ∈ is univalent in , then Fn(z) is starlike in |z| < 3/8. The number 3/8 is sharp....

In this paper the authors studied the coefficient estimate of a class of functions starlike with respect to k-symmetric points defined by derivative operators D n λ introduced by Al-Shaqsi and Darus [6]. The integral representation and several coefficient inequalities of functions belonging to this class are obtained. 1 Introduction Let A denote the class of functions of the form: f (z) = z + ∞...

In an earlier paper [l] the writer showed the development of a variational method for starlike functions and applied this method to a general class of extremal problems connected with the coefficients of the function. It is the purpose of this paper to study the classes of extremal problems to which this variational method can be applied and to make some remarks as to its utility. The class S* ...

1. In addition to the study devoted to the general class of normalized regular univalent functions in the unit circle considerable attention has been given to certain subclasses of these functions such as starlike functions, convex functions, and others. In view of the important role played by symmetrization methods in recent work it seems worth while to study a further subclass—the class of ci...

We construct polynomial norming meshes with optimal cardinality growth, on planar compact starlike domains that satisfy a Uniform Interior Ball Condition (UIBC). 2000 AMS subject classification: 41A10, 41A63, 65D05.

By using the method of differential subordinations, we derive certain sufficient conditions for strongly starlike functions associated with an integral operator. All these results presented here are sharp. 2000 Mathematics Subject Classification. Primary 30C45; Secondary 30A10.