In this paper we consider the class of Bazilevic functions for bi-univalent functions. For this we will estimate the coefficients a2 and a3 using Caratheodory func- tions and the method of differential subordination.
Motivated and stimulated especially by the work of Xu et al. [1], in this paper, we introduce and discuss an interesting subclass of analytic and bi-univalent functions defined in the open unit disc U. Further, we fin...Motivated and stimulated especially by the work of Xu et al. [1], in this paper, we introduce and discuss an interesting subclass of analytic and bi-univalent functions defined in the open unit disc U. Further, we find estimates on the coefficients and for functions in this subclass. Many relevant connections with known or new results are pointed out.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 this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell...In this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell shaped region in the open unit disc ?.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
In this paper, we introduce and investigate a new subclass of the function class ∑. of bi-univalent functions of the Mocanu-convex type defined in the open unit disk, satisfy Ma and Minda subordination conditions. Fu...In this paper, we introduce and investigate a new subclass of the function class ∑. of bi-univalent functions of the Mocanu-convex type defined in the open unit disk, satisfy Ma and Minda subordination conditions. Furthermore, we find estimates on the Taylor-Maclaurin coefficients |a2| and |a3| for functions in the new subclass introduced here. Further Application of Hohlov operator to this class is obtained. Several (known or new) consequences of the results are also pointed out.展开更多
In this paper, we introduce a new class of p-valent analytic functions defined by using a linear operator Lαk . For functions in this class Hαk (p,λ;h) we estimate the coefficients. Furthermore, some subordinatio...In this paper, we introduce a new class of p-valent analytic functions defined by using a linear operator Lαk . For functions in this class Hαk (p,λ;h) we estimate the coefficients. Furthermore, some subordination properties related to the operator Lαk are also derived.展开更多
For real numbers α and β such that 0≤α<1<β, we denote by T(α,β) the class of normalized analytic functions which satisfy , where U denotes the open unit disk. We find some relationships involving function...For real numbers α and β such that 0≤α<1<β, we denote by T(α,β) the class of normalized analytic functions which satisfy , where U denotes the open unit disk. We find some relationships involving functions in the class T(α,β). And we estimate the bounds of coefficients and solve Fekete-Szego problem for functions in this class. Furthermore, we investigate the bounds of initial coefficients of inverse functions or bi-univalent functions.展开更多
In the present paper, we introduce a class of analytic functions in the open unit disc by using the analytic function qα(z)=3/(3+(α-3)z-αz2), which was investigated by Sokó? [1]. We find some properties includ...In the present paper, we introduce a class of analytic functions in the open unit disc by using the analytic function qα(z)=3/(3+(α-3)z-αz2), which was investigated by Sokó? [1]. We find some properties including the growth theorem or the coefficient problem of this class and we find some relation with this new class and the class of convex functions.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
This article presents some new results on the class SLMα of functions that are analytic in the open unit disc U = {z : |z|〈 1} satisfying the conditions that f(0) =0, f'(0)= 1, and α(1+zf''(z)/f'(...This article presents some new results on the class SLMα of functions that are analytic in the open unit disc U = {z : |z|〈 1} satisfying the conditions that f(0) =0, f'(0)= 1, and α(1+zf''(z)/f'(z)+(1-α)zf'(z)/f(z)∈p(U)for all z ∈ U, where αis a real number and p(z)=1+r^2z^2/1-Tz-T^2z^2(z∈ U). The number T = (1 -√5)/2 is such that T^2 = 1 + T. The class SFLMa introduced by J. Dziok, R.K. Raina, and J. Sokot [3, Appl. Math. Comput. 218 (2011), 996-1002] is closely related to the classes of starlike and convex functions. The article deals with several ideas and techniques used in geometric function theory and differential subordinations theory.展开更多
The authors obtain subordination and superordination preserving properties for a new defined generalized operator involving the Srivastava-Attiya integral operator. Differential sandwich-type theorems for these unival...The authors obtain subordination and superordination preserving properties for a new defined generalized operator involving the Srivastava-Attiya integral operator. Differential sandwich-type theorems for these univalent functions, and some consequences involving well-known special functions are also presented.展开更多
文摘In this paper we consider the class of Bazilevic functions for bi-univalent functions. For this we will estimate the coefficients a2 and a3 using Caratheodory func- tions and the method of differential subordination.
文摘Motivated and stimulated especially by the work of Xu et al. [1], in this paper, we introduce and discuss an interesting subclass of analytic and bi-univalent functions defined in the open unit disc U. Further, we find estimates on the coefficients and for functions in this subclass. Many relevant connections with known or new results are pointed out.
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.
文摘In this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell shaped region in the open unit disc ?.
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In this paper, we introduce and investigate a new subclass of the function class ∑. of bi-univalent functions of the Mocanu-convex type defined in the open unit disk, satisfy Ma and Minda subordination conditions. Furthermore, we find estimates on the Taylor-Maclaurin coefficients |a2| and |a3| for functions in the new subclass introduced here. Further Application of Hohlov operator to this class is obtained. Several (known or new) consequences of the results are also pointed out.
文摘In this paper, we introduce a new class of p-valent analytic functions defined by using a linear operator Lαk . For functions in this class Hαk (p,λ;h) we estimate the coefficients. Furthermore, some subordination properties related to the operator Lαk are also derived.
基金supported by Kyungsung University Re-search Grants in 2013.
文摘For real numbers α and β such that 0≤α<1<β, we denote by T(α,β) the class of normalized analytic functions which satisfy , where U denotes the open unit disk. We find some relationships involving functions in the class T(α,β). And we estimate the bounds of coefficients and solve Fekete-Szego problem for functions in this class. Furthermore, we investigate the bounds of initial coefficients of inverse functions or bi-univalent functions.
文摘In the present paper, we introduce a class of analytic functions in the open unit disc by using the analytic function qα(z)=3/(3+(α-3)z-αz2), which was investigated by Sokó? [1]. We find some properties including the growth theorem or the coefficient problem of this class and we find some relation with this new class and the class of convex functions.
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}.
文摘This article presents some new results on the class SLMα of functions that are analytic in the open unit disc U = {z : |z|〈 1} satisfying the conditions that f(0) =0, f'(0)= 1, and α(1+zf''(z)/f'(z)+(1-α)zf'(z)/f(z)∈p(U)for all z ∈ U, where αis a real number and p(z)=1+r^2z^2/1-Tz-T^2z^2(z∈ U). The number T = (1 -√5)/2 is such that T^2 = 1 + T. The class SFLMa introduced by J. Dziok, R.K. Raina, and J. Sokot [3, Appl. Math. Comput. 218 (2011), 996-1002] is closely related to the classes of starlike and convex functions. The article deals with several ideas and techniques used in geometric function theory and differential subordinations theory.
文摘The authors obtain subordination and superordination preserving properties for a new defined generalized operator involving the Srivastava-Attiya integral operator. Differential sandwich-type theorems for these univalent functions, and some consequences involving well-known special functions are also presented.