TY - JOUR T1 - Inequalities for the Polar Derivatives of a Polynomial JO - Analysis in Theory and Applications VL - 4 SP - 425 EP - 432 PY - 2014 DA - 2014/11 SN - 30 DO - http://doi.org/10.4208/ata.2014.v30.n4.10 UR - https://global-sci.org/intro/article_detail/ata/4507.html KW - Polar derivative of a polynomial, maximum modulus, Bernstein's inequality. AB -

Let $P(z)$ be a polynomial of degree $n,$ having all its zeros in $|z|\leq 1.$ In this paper, we estimate $kth$ polar derivative of $P(z)$ on $|z|=1$ and thereby obtain compact generalizations of some known results which among other things yields a refinement of a result due to Paul TurĂ¡n.