In this paper, we investigate the coefficient estimates of a class of m-fold bi-univalent function de?ned by subordination. The results presented in this paper improve or generalize the recent works of other authors.
The aim of this paper is to establish the Fekete-Szego inequality for a subclass of bi-univalent strongly quasi-starlike functions which is defined in the open unit disk. Furthermore, the coefficients a2 and a3 for fu...The aim of this paper is to establish the Fekete-Szego inequality for a subclass of bi-univalent strongly quasi-starlike functions which is defined in the open unit disk. Furthermore, the coefficients a2 and a3 for functions in this new subclass are estimated.展开更多
In this paper, we investigate the bounds of the coefficients of several classes of bi-univalent functions. The results presented in this paper improve of generalize the recent works of other authors.
Let A be the space of functions analytic in the unit disk D = {z:|z| 〈 1}.Let U denote the set of all functions f ∈ A satisfying the conditions f(0) = f'(0)-1 = 0 and|f'(z)(z/f(z))2-1|〈1(|z|〈1...Let A be the space of functions analytic in the unit disk D = {z:|z| 〈 1}.Let U denote the set of all functions f ∈ A satisfying the conditions f(0) = f'(0)-1 = 0 and|f'(z)(z/f(z))2-1|〈1(|z|〈1).Also,let Ω denote the set of all functions f ∈ A satisfying the conditions f(0) = f'(0)-1 = 0and|zf'(z)-f(z)|〈1/2(|z|〈1).In this article,we discuss the properties of U and Ω.展开更多
In the present paper, we derive some third-order differential subordination results for analytic functions in the open unit disk, using the operator Bcκf by means of normalized form of the generalized Bessel function...In the present paper, we derive some third-order differential subordination results for analytic functions in the open unit disk, using the operator Bcκf by means of normalized form of the generalized Bessel functions of the first kind, which is defined as z(Bκ+1^c f(z))′= κBκ^c f(z)-(κ- 1)Bκ+1^c f(z),where b, c, p ∈ C and κ = p +(b + 1)/2 ∈ C / Z0^-(Z0^-= {0,-1,-2, … }). The results are obtained by considering suitable classes of admissible functions. Various known or new special cases of our main results are also pointed out.展开更多
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
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
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 investigate a subordination property and the coefficient inequality for the class M(1, b), The lower bound is also provided for the real part of functions belonging to the class M(1, b).
In this paper we introduce a new general subclass n,G∑ a,λ(A, B, α) of univalent functions related the known integral operator and differential operator. Some majorization results for n,G∑ a,λ(A, B, 1) as well as...In this paper we introduce a new general subclass n,G∑ a,λ(A, B, α) of univalent functions related the known integral operator and differential operator. Some majorization results for n,G∑ a,λ(A, B, 1) as well as the other functions are given. Furthermore, we find the coefficients bounds on |a_2| and |a_3| for functions in*n,G∑ a,λ(A_1, B_1, A_2, B_2, α_1, α_2), which is the bi-univalent functions defined by n,G ∑a,λ(A, B, α) and subordination. By giving specific values of the parameters of our main results, several(known or new) consequences of main results are also discussed.展开更多
This paper discusses the function class Hβ(a) of the from f(z)=z+∑k=(n+1)^+∞, which satisfies the conditon Re[f'(Z)+βzf″(z)]>a, (0≤a<1) in |z|<1, with its inclusion relation ,neighborhood properties and t...This paper discusses the function class Hβ(a) of the from f(z)=z+∑k=(n+1)^+∞, which satisfies the conditon Re[f'(Z)+βzf″(z)]>a, (0≤a<1) in |z|<1, with its inclusion relation ,neighborhood properties and the deviation theorem ,convolution properties in the case when f(z) has negative coefficients.展开更多
In the paper we introduce an idea of harmonic functions with correlated coefficients which generalize the ideas of harmonic functions with negative coefficients introduced by Silverman and harmonic functions with vary...In the paper we introduce an idea of harmonic functions with correlated coefficients which generalize the ideas of harmonic functions with negative coefficients introduced by Silverman and harmonic functions with varying coefficients defined by Jahangiri and Silverman. Next we define classes of harmonic functions with correlated coefficients in terms of generalized Dziok-Srivastava operator. By using extreme points theory, we obtain estimations of classical convex functionals on the defined classes of functions. Some applications of the main results are also considered.展开更多
Making use of the Carlson-Shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficie...Making use of the Carlson-Shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficient bound for this class. We also show that this class is closed under convolution with a convex function. Some applications are also discussed.展开更多
We introduce a new class of complex valued harmonic functions associated with Wright hypergeometric functions which are orientation preserving and univalent in the open unit disc. Further we define, Wright generalized...We introduce a new class of complex valued harmonic functions associated with Wright hypergeometric functions which are orientation preserving and univalent in the open unit disc. Further we define, Wright generalized operator on harmonic function and investigate the coefficient bounds, distortion inequalities and extreme points for this generalized class of functions.展开更多
We investigate some new subclasses of analytic functions of Janowski type of complex order.We also study inclusion properties,distortion theorems,coefficient bounds and radius of convexity of the functions.Moreover,an...We investigate some new subclasses of analytic functions of Janowski type of complex order.We also study inclusion properties,distortion theorems,coefficient bounds and radius of convexity of the functions.Moreover,analytic properties of these classes under certain integral operator are also discussed.Our findings are more comprehensive than the existing results in the literature.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
Making use of a multiplier transformation, which is defined by means of the Hadamard product (or convolution), we introduce some new subclasses of analytic functions and investigate their inclusion relationships and a...Making use of a multiplier transformation, which is defined by means of the Hadamard product (or convolution), we introduce some new subclasses of analytic functions and investigate their inclusion relationships and argument properties.展开更多
Let An(p)(p,n ∈ N = {1,2,3,...}) denote the class of functions of the form f(z) = zp +ap+nzp+n +...which are analytic in the unit disk E = {z:|z| < 1}.A function f(z) in A(p) is said to be in the class Sp(a,b) if ...Let An(p)(p,n ∈ N = {1,2,3,...}) denote the class of functions of the form f(z) = zp +ap+nzp+n +...which are analytic in the unit disk E = {z:|z| < 1}.A function f(z) in A(p) is said to be in the class Sp(a,b) if it satisfies zf(z) pf(z) 1 + az 1 + bz for some a and b(-1 ≤ b < a ≤ 1).In this paper,using the method of differential subordinations,we give new criteria for f(z) to be in the classes Sp(a,b)(-1 ≤ b < a ≤ 1),that is,if f(z) ∈ A(p) satisfies f(z) = 0 in 0 < |z| < 1,f(z) = 0 when μ = 1,and zf(z) f(z) μ 1 + zff((zz)) + λzff(z(z))h(z),where h(z) = p1+μ(1 + λ) 11 ++ abzz 1+μ + pμ(1 + az)1-μ(1+bz)1+μ,λ≥-1,μ∈ {-1,0,1},then f(z) ∈ Sp(a,b).Our results improve or extend some results due to Owa,Nunokawa,Padmanabhan,Silverman,Obradovic,Yang and others[3-10].展开更多
基金The NSF(KJ2018A0839,KJ2018A0833) of Anhui Provincial Department of Education
文摘In this paper, we investigate the coefficient estimates of a class of m-fold bi-univalent function de?ned by subordination. The results presented in this paper improve or generalize the recent works of other authors.
基金The NSF(KJ2018A0833)of Anhui Provincial Department of Educationthe Scientific Research Foundation(17X0413)of Guangzhou Civil Aviation College
文摘The aim of this paper is to establish the Fekete-Szego inequality for a subclass of bi-univalent strongly quasi-starlike functions which is defined in the open unit disk. Furthermore, the coefficients a2 and a3 for functions in this new subclass are estimated.
基金supported by NSFC(11071058)Educational Commission of Hubei Province of China(D2011006)
文摘In this paper, we investigate the bounds of the coefficients of several classes of bi-univalent functions. The results presented in this paper improve of generalize the recent works of other authors.
基金Supported by the Key Laboratory of Applied Mathematics in Hubei Province,China
文摘Let A be the space of functions analytic in the unit disk D = {z:|z| 〈 1}.Let U denote the set of all functions f ∈ A satisfying the conditions f(0) = f'(0)-1 = 0 and|f'(z)(z/f(z))2-1|〈1(|z|〈1).Also,let Ω denote the set of all functions f ∈ A satisfying the conditions f(0) = f'(0)-1 = 0and|zf'(z)-f(z)|〈1/2(|z|〈1).In this article,we discuss the properties of U and Ω.
基金partly supported by the Natural Science Foundation of China(11271045)the Higher School Doctoral Foundation of China(20100003110004)+2 种基金the Natural Science Foundation of Inner Mongolia of China(2010MS0117)athe Higher School Foundation of Inner Mongolia of China(NJZY13298)the Commission for the Scientific Research Projects of Kafkas Univertsity(2012-FEF-30)
文摘In the present paper, we derive some third-order differential subordination results for analytic functions in the open unit disk, using the operator Bcκf by means of normalized form of the generalized Bessel functions of the first kind, which is defined as z(Bκ+1^c f(z))′= κBκ^c f(z)-(κ- 1)Bκ+1^c f(z),where b, c, p ∈ C and κ = p +(b + 1)/2 ∈ C / Z0^-(Z0^-= {0,-1,-2, … }). The results are obtained by considering suitable classes of admissible functions. Various known or new special cases of our main results are also pointed out.
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 investigate a subordination property and the coefficient inequality for the class M(1, b), The lower bound is also provided for the real part of functions belonging to the class M(1, b).
基金Supported by the Scientific Research Found of Education Department of Sichuan Province(14ZB0364)
文摘In this paper we introduce a new general subclass n,G∑ a,λ(A, B, α) of univalent functions related the known integral operator and differential operator. Some majorization results for n,G∑ a,λ(A, B, 1) as well as the other functions are given. Furthermore, we find the coefficients bounds on |a_2| and |a_3| for functions in*n,G∑ a,λ(A_1, B_1, A_2, B_2, α_1, α_2), which is the bi-univalent functions defined by n,G ∑a,λ(A, B, α) and subordination. By giving specific values of the parameters of our main results, several(known or new) consequences of main results are also discussed.
文摘This paper discusses the function class Hβ(a) of the from f(z)=z+∑k=(n+1)^+∞, which satisfies the conditon Re[f'(Z)+βzf″(z)]>a, (0≤a<1) in |z|<1, with its inclusion relation ,neighborhood properties and the deviation theorem ,convolution properties in the case when f(z) has negative coefficients.
基金supported by the Centre for Innovation and Transfer of Natural Sciences and Engineering Knowledge,University of Rzeszów
文摘In the paper we introduce an idea of harmonic functions with correlated coefficients which generalize the ideas of harmonic functions with negative coefficients introduced by Silverman and harmonic functions with varying coefficients defined by Jahangiri and Silverman. Next we define classes of harmonic functions with correlated coefficients in terms of generalized Dziok-Srivastava operator. By using extreme points theory, we obtain estimations of classical convex functionals on the defined classes of functions. Some applications of the main results are also considered.
文摘Making use of the Carlson-Shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficient bound for this class. We also show that this class is closed under convolution with a convex function. Some applications are also discussed.
文摘We introduce a new class of complex valued harmonic functions associated with Wright hypergeometric functions which are orientation preserving and univalent in the open unit disc. Further we define, Wright generalized operator on harmonic function and investigate the coefficient bounds, distortion inequalities and extreme points for this generalized class of functions.
文摘We investigate some new subclasses of analytic functions of Janowski type of complex order.We also study inclusion properties,distortion theorems,coefficient bounds and radius of convexity of the functions.Moreover,analytic properties of these classes under certain integral operator are also discussed.Our findings are more comprehensive than the existing results in the literature.
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.
文摘Making use of a multiplier transformation, which is defined by means of the Hadamard product (or convolution), we introduce some new subclasses of analytic functions and investigate their inclusion relationships and argument properties.
基金Supported by the Natural Science Foundation of Jiangsu Education Department(06KJD110003)
文摘Let An(p)(p,n ∈ N = {1,2,3,...}) denote the class of functions of the form f(z) = zp +ap+nzp+n +...which are analytic in the unit disk E = {z:|z| < 1}.A function f(z) in A(p) is said to be in the class Sp(a,b) if it satisfies zf(z) pf(z) 1 + az 1 + bz for some a and b(-1 ≤ b < a ≤ 1).In this paper,using the method of differential subordinations,we give new criteria for f(z) to be in the classes Sp(a,b)(-1 ≤ b < a ≤ 1),that is,if f(z) ∈ A(p) satisfies f(z) = 0 in 0 < |z| < 1,f(z) = 0 when μ = 1,and zf(z) f(z) μ 1 + zff((zz)) + λzff(z(z))h(z),where h(z) = p1+μ(1 + λ) 11 ++ abzz 1+μ + pμ(1 + az)1-μ(1+bz)1+μ,λ≥-1,μ∈ {-1,0,1},then f(z) ∈ Sp(a,b).Our results improve or extend some results due to Owa,Nunokawa,Padmanabhan,Silverman,Obradovic,Yang and others[3-10].