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1Unite of Biomathematics, College of Computer Science and Mathematics, University of Al-Qadisiya, Diwiniya- ... In this paper, we introduce a class of functions.
Asian Journal of Current Engineering and Maths 2: 1 Jan –Feb (2013) 10 - 14.

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SOME PROPERTIES FOR CERTAIN CLASS OF P-VALENT FUNCTIONS INVOLVING NOOR OPERATOR WITH DIFFERENTIAL EQUATION Ahmed sallal Joudah, Jumana Hekma Salman* 1Unite

of Biomathematics, College of Computer Science and Mathematics, University of Al-Qadisiya, Diwiniya- Iraq

2Department

of Statistical and Informatics, College of Computer Science and Mathematics, University of Al-Qadisiya, Diwiniya- Iraq

ARTICLE INFO

ABSTRACT

Corresponding Author Jumana Hekma Salman 2Department of Statistical and Informatics, College of Computer Science and Mathematics, University of Al-Qadisiya, Diwiniya- Iraq Key Words: Differential Subordination,Multivalent function,Cauchy-Euler differential equation. INTRODUCTION Let

In this paper, we introduce a class of functions (C,B) which are analytic and p-valent in the unit disk U. We obtain a necessary and sufficient condition for a function to be in (C,B) ,distortion bounds and convex combination. 2010 Mathematics Subject Classification: Primary 30C45, Secondary 30C50,26A33.

©2013, AJCEM, All Right Reserved.

denote the family of all functions ,of the form:

which are analytic and p-valent in the open unit disk point in . For functions given by:

We define the Hadamard product(or convolution) of

,and

and

by:

Suppose that and are analytic in . Then we say that the functions function in with for all ,such that is equivalent to univalent in we have that the subordination For real or complex number defined by

is a fixed

is subordinate to ,denoted or and

, the hypergeometric series is

F

2 1

We note that the series in (3) converges absolutely for all analytic function in . The authors [3] introduced a function

F

so that it represents and given by

2 1

F

F

2 1

2 1

which leads us to the following family of linear operators:

F

2 1

10

if there exists an analytic . In case is .

Salman et. al/ Some Properties For Certain Class Of P-Valent Functions Involving Noor Operator With Differential Equation

.It is evident that was define recently by Cho et al. [2], is the Noor integral operator .The operator was investigation by was introduced by Liu and Noor[4] (see also[5]), and Saitoh [8]. By some easy calculations we obtain where

where

denote the pochhammer symbol defined by:

Note that the operator

was defined recently by [1].

By using the Noor integral operator as follows:

, we now define certain Class of

Definition 1. For fixed parameters and ,with satisfies the following subordination condition:

Or equivalently ,

is in the class

,we say that

if and only if

where and is given by (6). Here, we shall obtain several interesting results on the functions which are defined by the class following non homogeneous Cauchy-Euler differential equation:

where 

 k n

. By using the equation(3) and the following definition

where the operator

is the saigo type fractional calculus operator ([6],see also[7]) and is defined sa follows:

Definition 2. For 2

F1

2. Necessary and Sufficient condition for Theorem 1.Let the functions

where

if it

be given by (1), then

if and only if

Then result (12) is sharp for the functions

Proof. For the sufficient condition ,suppose that the inequality(12) hold true and

11

Then we obtain

with the

Salman et. al/ Some Properties For Certain Class Of P-Valent Functions Involving Noor Operator With Differential Equation

(14)

Hence, by maximum modulus theorem for on

this implies be given by(1), then from (8), we find that

For necessary condition, let



 k n



 k n

Now ,since

we have 

 k n



 k n

We can choose value of

on the real axis and all allowing

Finally, sharpness follow if we take given by (13). Corollary 1.Let the function be given by (1) .If

,through real values , so we can write (15) as

then

The result is sharp for the function given by (13). Theorem 2.If

is in the class

then

and

proof. Suppose that is given by (1).Also let the function ,occuring in the non homogeneous Cauchy-Euler differential equation (9).Then we reaeadily find from (9) that

12

Salman et. al/ Some Properties For Certain Class Of P-Valent Functions Involving Noor Operator With Differential Equation

so that

and

Next since

,the first assertion (16)of Corollary 1 yields the following coefficient inequality

which in conjunction with (20),yields

Finally ,in view of the following telescopic sum:

The first assertion (17)of Theorem (2)follows at once from (22).The second assertion (18) of Theorem (2)can be prove by similarly applying (20),(21)and (23). Theorem 3. Let a function

be in the class

.Then we have

and

proof. Using Theorem 1 we have

or

From equation (10),we get

Using (26),(27) and (19) we have

which is equivalent to(24) and

13

Salman et. al/ Some Properties For Certain Class Of P-Valent Functions Involving Noor Operator With Differential Equation

which gives (25). is closed under linear combination .

In the following theorem , we will show that the class be given by (2) .

Theorem 4.Let

and

such that

t



where

j1

Then the function

is also in the class Proof. For every

we obtain

Using (28), we get

There fore

Hence REFERENCE [1]. M.Ç ǴL R H.ORH N and E.ENIZ Majorization for certain subclasses of analytic functions involving the generalized Noor integral operator ,Filomat ,27(2013),134-139. [2] N.E. Cho, O.S. Kwon and H. M. Srivastava , Inclusion relationships and argument properties for certain subclasses of multivalent functions associated with a family of linear operators, J. Math. Anal. Appl. 292 (2004) 470-483. [3] X. L. Fu, M. S. Liu, Some subclasses of analytic functions involving the generalized Noor integral operator, J. Math. Anal. Appl. 323 (2006) 190-208. [4] J.L. Liu, K. I. Noor, Some properties of Noor integral operator, J. Nat. Geom. 21 (2002), 81-90. [5] J. Patel, N.E. Cho, Some classes of analytic functions involving Noor integral operator, J .Math. Anal. Appl. 312 (2005) 564-575. [6] R.K.Raina and T.S.Nahar, Informatica (Lithuanian Acad. Sci)9(1998)469-478. [7] R.K.Raina and H.M.Srivastava , compute .Math Appl.32(1996)13-19 . [8] H. Saitoh, A linear operator and its application of first order differential subordinations, Math. Japon. 44 (1996) 31-38. [9] S.G.Samko, A.A.Kilbas and O.I.Marichev, Fractional integrals and Derivatives: Theory and Applications, Gordon and Breach Science publishers, Reading Tokyo, Paris,Berlinand Langhorne(Pennsylvania)1993 .

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