SOME RESULTS ON JACK’S LEMMA FOR ANALYTIC FUNCTIONS

Year 2022, Volume: 3 Issue: 2, 31 - 40, 31.12.2022

Bülent Nafi Örnek

https://doi.org/10.54559/jauist.1207927

Abstract

In this paper, an upper bound will be found for the second coefficient in the Taylor expansion of the analytical function $p(z)$ using the Jack lemma. Also, the modulus of the angular derivative of the $I_{f}(z)=\frac{zp^{\prime }(z)}{p(z)}$ function on the unit disc will be estimated from below.

Keywords

Analytic function, Jack’s lemma, Schwarz lemma.

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