The purpose of this article is to obtain some subordination and superordi- nation preserving properties of meromorphic multivalent functions in the punctured open unit disk associated with the Liu-Srivastava operator....The purpose of this article is to obtain some subordination and superordi- nation preserving properties of meromorphic multivalent functions in the punctured open unit disk associated with the Liu-Srivastava operator. The sandwich-type results for these meromorphic multivalent functions are also considered.展开更多
For real parameters αand β such that 0≤α 〈 1 〈β, we denote by S(α,β) the class of normalized analytic functions which satisfy the following two-sided inequality:where U denotes the open unit disk. We find ...For real parameters αand β such that 0≤α 〈 1 〈β, we denote by S(α,β) the class of normalized analytic functions which satisfy the following two-sided inequality:where U denotes the open unit disk. We find a sufficient condition for functions to be in the class S(α,β) and solve several radius problems related to other well-known function classes.展开更多
In the present paper, we obtain some subordination- and superordinatiompreserving properties of certain integral operators defined on the space of normalized analytic functions in the open unit disk. The sandwich-type...In the present paper, we obtain some subordination- and superordinatiompreserving properties of certain integral operators defined on the space of normalized analytic functions in the open unit disk. The sandwich-type theorems for these integral operators are also considered.展开更多
Given α∈[0, 1], let hα(z) := z/(1 - αz), z ∈ D := {z ∈ C: |z| 〈 1}. An analytic standardly normalized function f in D is called close-to-convex with respect to hα if there exists δ ∈ (-π/2, π/2)...Given α∈[0, 1], let hα(z) := z/(1 - αz), z ∈ D := {z ∈ C: |z| 〈 1}. An analytic standardly normalized function f in D is called close-to-convex with respect to hα if there exists δ ∈ (-π/2, π/2) such that Re{e^iδ zf′(z)/hα(z)} 〉 0, z ∈ D. For the class l(hα) of all close-to-convex functions with respect to hα, the Fekete-Szego problem is studied.展开更多
The old result due to[Ozaki,S.:On the theory of multivalent functions Ⅱ.Sci.Rep.Tokyo Bunrika Daigaku Sect.A,45-87(1941)],says that if f(z) = zp + ∑n=p+1anzn∞ is analytic in a convex domain D and for some re...The old result due to[Ozaki,S.:On the theory of multivalent functions Ⅱ.Sci.Rep.Tokyo Bunrika Daigaku Sect.A,45-87(1941)],says that if f(z) = zp + ∑n=p+1anzn∞ is analytic in a convex domain D and for some real α we have Re{exp(iα)f(p)(z)}〉 0 in D,then f(z) is at most p-valent in ED.In this paper,we consider similar problems in the unit disc B = {z ∈ C:|z| 〈 1}.展开更多
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education,Science and Technology (2010-0017111)
文摘The purpose of this article is to obtain some subordination and superordi- nation preserving properties of meromorphic multivalent functions in the punctured open unit disk associated with the Liu-Srivastava operator. The sandwich-type results for these meromorphic multivalent functions are also considered.
文摘For real parameters αand β such that 0≤α 〈 1 〈β, we denote by S(α,β) the class of normalized analytic functions which satisfy the following two-sided inequality:where U denotes the open unit disk. We find a sufficient condition for functions to be in the class S(α,β) and solve several radius problems related to other well-known function classes.
基金Supported by the Korea Research Foundation from the Korean Government (MOEHRD, Basic Research Promotion Fund) (Grant No. KRF-2008-313-C00035)
文摘In the present paper, we obtain some subordination- and superordinatiompreserving properties of certain integral operators defined on the space of normalized analytic functions in the open unit disk. The sandwich-type theorems for these integral operators are also considered.
文摘Given α∈[0, 1], let hα(z) := z/(1 - αz), z ∈ D := {z ∈ C: |z| 〈 1}. An analytic standardly normalized function f in D is called close-to-convex with respect to hα if there exists δ ∈ (-π/2, π/2) such that Re{e^iδ zf′(z)/hα(z)} 〉 0, z ∈ D. For the class l(hα) of all close-to-convex functions with respect to hα, the Fekete-Szego problem is studied.
基金Supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(Grant No.2011-0007037)
文摘The old result due to[Ozaki,S.:On the theory of multivalent functions Ⅱ.Sci.Rep.Tokyo Bunrika Daigaku Sect.A,45-87(1941)],says that if f(z) = zp + ∑n=p+1anzn∞ is analytic in a convex domain D and for some real α we have Re{exp(iα)f(p)(z)}〉 0 in D,then f(z) is at most p-valent in ED.In this paper,we consider similar problems in the unit disc B = {z ∈ C:|z| 〈 1}.