Abstract
Let P(z) be a polynomial of degree n having all its zeros in \(|z|\le 1\), then according to Turan (Compositio Mathematica 7:89–95, 2004)
In this paper, we shall use polar derivative and establish a generalisation and an extension of this result. Our results also generalize variety of other results.
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Acknowledgements
This work was supported by NBHM, India, under the research project number 02011/36/2017/R&D-II.
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Gulzar, M.H., Zargar, B.A. & Akhter, R. Inequalities for the polar derivative of a polynomial. J Anal 28, 923–929 (2020). https://doi.org/10.1007/s41478-020-00222-4
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DOI: https://doi.org/10.1007/s41478-020-00222-4