A lower bound for the L_2[-1,1]-norm of the logarithmic derivative of polynomials with zeros on the unit circle
Journal Title: Проблемы анализа-Issues of Analysis - Year 2019, Vol 8, Issue 2
Abstract
Let C be the unit circle {z:|z|= 1} and Qn(z) bean arbitrary C-polynomial (i. e., all its zeros z1, . . ., zn ∈ C). We prove that the norm of the logarithmic derivative Q′n/Qn in the complex space L2[−1,1] is greater than 1/8.
Authors and Affiliations
M . A . Komarov
Keywords
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- EP ID EP593212
- DOI 10.15393/j3.art.2019.6030
- Views 81
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