Point-wise estimates for the derivative of algebraic polynomials

  • A. V. Savchuk Taras Shevchenko National University of Kyiv
Keywords: algebraic polynomial; logarithmic derivative; Bernstein’s inequality


We give a sufficient condition on coefficients $a_k$ of an algebraic polynomial $P(z)=\sum\limits_{k=0}^{n}a_kz^k$, $a_n\not=0,$ such that the pointwise Bernstein inequality $|P'(z)|\le n|P(z)|$ is true for all $z,\ |z|\le 1$.


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How to Cite
Savchuk, A. V. (2021). Point-wise estimates for the derivative of algebraic polynomials. Matematychni Studii, 56(2), 208-211. https://doi.org/10.30970/ms.56.2.208-211
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