Some Results on Starlike and Convex Functions

نویسنده

  • Nikola Tuneski
چکیده

Let A denotes the class of functions f(z) that are analytic in the unit disk U = {z : |z| < 1} and normalized by f(0) = f ′(0)− 1 = 0. Further, let f, g ∈ A. Then we say that f(z) is subordinate to g(z), and we write f(z) ≺ g(z), if there exists a function ω(z), analytic in the unit disk U , such that ω(0) = 0, |ω(z)| < 1 and f(z) = g(ω(z)) for all z ∈ U . Specially, if g(z) is univalent in U then f(z) ≺ g(z) if and only if f(0) = g(0) and f(U) ⊆ g(U). If −1 ≤ B < A ≤ 1 then an important class is defined by

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تاریخ انتشار 2007