The Distortion Theorems for Harmonic Mappings with Analytic Parts Convex or Starlike Functions of Orderβ

Robin functions and distortion theorems for regular mappings

Capacities of generalized condensers are applied to prove a two-point distortion theorem for conformal mappings. The result is expressed in terms of the Robin function and the Robin capacity with respect to the domain of definition of the mapping and subsets of the boundary of this domain. The behavior of Robin function under multivalent functions is studied. Some corollaries and examples of ap...

Distortion Theorems for a Special Class of Analytic Functions

Sharp bounds are derived for the derivative of analytic functions of class .P,, defined by the condition |/>(z) —l/2a|<: l/2a, O^a^l, p(f>) = \. These results are improved for the class of functions with missing terms. Application is made to the class of functions with derivative G Px and the radius of convexity is determined for this class.

On Sandwich theorems for certain classes of analytic functions

The purpose of this present paper is to derive some subordination and superordination results for certain analytic functions in the open unit disk. Relevant connections of the results, which are presented in the paper, with various known results are also considered.

On Certain Multivalent Starlike or Convex Functions with Negative Coefficients

Angle distortion theorems for starlike and spirallike functions with respect to a boundary point

It is clear that 0∈ h(Δ). Moreover, (i) if 0 ∈ h(Δ), then h is called spirallike (resp., starlike) with respect to an interior point; (ii) if 0 ∈ h(Δ), then h is called spirallike (resp., starlike) with respect to a boundary point. In this case, there is a boundary point (say, z = 1) such that h(1) := ∠ limz→1h(z)= 0 (see, e.g., [1, 6]); by symbol∠ lim, we denote the angular (nontangential) lim...