PRODUCT AND CONVOLUTION OF CERTAIN UNIVALENT FUNCTIONS = PRODUCT AND CONVOLUTION OF CERTAIN UNIVALENT FUNCTIONS

다국어 초록 (Multilingual Abstract)

For f_i belonging to various subclasses of univalent func- tions, we investigate the product given by h(z) =zII _{i=1} ^{n} (f _{i} (z)/z) ^{yi} . The largest radius ½ is determined such that h(½z)=½ is starlike of orderβ, 0 · β < 1 or to belong to other subclasses of univalent functions. We also determine the sharp radius of starlikeness of order β and other radius for the convolution f ¤ g of two starlike functions f; g.

참고문헌 (Reference)

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