On Certain Multivalent Starlike or Convex Functions with Negative Coefficients
© Neslihan Uyanik et al. 2010
Received: 2 April 2010
Accepted: 3 June 2010
Published: 15 June 2010
By means of a differential operator, we introduce and investigate some new subclasses of -valently analytic functions with negative coefficients, which are starlike or convex of complex order. Relevant connections of the definitions and results presented in this paper with those obtained in several earlier works on the subject are also pointed out.
If we take and for , then become the differential operator defined by S l gean .
( ) and , were introduced by Srivastava et al. .
( ) and , were introduced by Silverman .
( ) and were introduced by Parvathan and Ponnusanny [6, pages 163-164].
( ) For and , the classes , , and are closely related with , , and which are defined by Owa and Sălăgean in .
In this paper we give relationships between the classes of , , and In the particular case when and , , and , we obtain the same results as in .
2. Main Results
Our main results are contained in
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