On Sakaguchi Functions

نویسندگان

  • DING-GONG YANG
  • JIN-LIN LIU
چکیده

Let Ss(α) (0≤α< 1/2) be the class of functions f(z)= z+··· which are analytic in the unit disk and satisfy there Re{zf ′(z)/(f (z)−f(−z))} > α. In the present paper, we find the sharp lower bound on Re{(f (z)−f(−z))/z} and investigate two subclasses S0(α) and T0(α) of Ss(α). We derive sharp distortion inequalities and some properties of the partial sums for functions in the classes S0(α) and T0(α).

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

On Sakaguchi-Type Harmonic Univalent Functions

We consider the Sakaguchi functions which are starlike with respect to symmetrical points in the open unit disk U and extend it to class SH(α, t) concerning with Sakaguchi-type complex-valued harmonic univalent functions in U. A sufficient coefficient condition and a necessary and sufficient convolution characterization for such harmonic functions are determined. In addition, by using the coeff...

متن کامل

Certain Coefficient Inequalities for Sakaguchi Type Functions and Applications to Fractional Derivatives

In the present paper, sharp upper bounds of |a3 −μa2| for the functions f(z) = z + a2z + a3z + · · · belonging to a new subclass of Sakaguchi type functions are obtained. Also, application of our results for subclass of functions defined by convolution with a normalized analytic function are given. In particular, Fekete-Szegö inequalities for certain classes of functions defined through fractio...

متن کامل

Coefficient Inequality for a Sub-class of Generalized Sakaguchi Type Functions

In this paper, we investigated the upper bounds of |a3 − μa2|, μ real, for a subclass of generalized Sakaguchi type functions of the form f(z) = z + ∑∞ n=2 anz n, in the unit disc E = {z : |z| < 1}. Results due to various authors follows as special cases. 2010 Mathematics Subject Classification. 30C50.

متن کامل

ACTA UNIVERSITATIS APULENSIS No 19/2009 CERTAIN COEFFICIENT INEQUALITIES FOR SAKAGUCHI TYPE FUNCTIONS AND APPLICATIONS TO FRACTIONAL DERIVATIVE OPERATOR

In the present paper, sharp upper bounds of |a3 − μa2| for the functions f(z) = z+ a2z + a3z + ... belonging to a new subclass of Sakaguchi type functions are obtained. Also, application of our results for subclass of functions defined by convolution with a normalized analytic function are given. In particular, Fekete-Szegö inequalities for certain classes of functions defined through fractiona...

متن کامل

Differential subordination and argumental property

For analytic functions f (z) in the open unit disk E and convex functions g(z) in E, has proved one theorem which is a generalization of the result by K. Sakaguchi [K. Sakaguchi, On a certain univalent mapping, J. Math. Soc. Japan 11 (1959) 72–75]. The object of the present paper is to generalize the theorem due to Pommerenke.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2002