Sufficient Conditions for Bounded Turning of Analytic Functions
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Consider a function f analytic in the open unit disk and normalized so that f(0) = f′(0) − 1 = 0. The methods of the theory of first-order differential subordinations are used to obtain sufficient conditions for the function f to have bounded turning, i.e., for the real part of its first derivative to map the unit disk onto the right half plane. In addition, several open problems are posed.
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