Coefficient Bounds for Certain Classes of Meromorphic Functions
نویسندگان
چکیده
Sharp bounds for |a1 − μa0| are derived for certain classes Σ∗ φ and Σα φ of meromorphic functions f z defined on the punctured open unit disk for which −zf ′ z /f z and − 1 − 2α zf ′ z αz2f ′′ z / 1 − α f z − αzf ′ z α ∈ C − 0, 1 ; R α ≥ 0 , respectively, lie in a region starlike with respect to 1 and symmetric with respect to the real axis. Also, certain applications of the main results for a class of functions defined through Ruscheweyh derivatives are obtained.
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