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arXiv · 2310.13531

Extremal problems of weighted approximation on the real axis

V. V. Savchuk·S. O. Chaichenko·A. L. Shidlich
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Abstract

We calculated the exact value and found the polynomial of the best weighted polynomial approximation of the kernels of the form $\frac {A+Bx}{(x^2+\lambda^2)^2}$, where $A,B\in {\mathbb R}$, $\lambda>0$ in the mean-square metric.

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V. V. Savchuk, S. O. Chaichenko, A. L. Shidlich. 2023-10-20. Extremal problems of weighted approximation on the real axis. https://arxiv.org/abs/2310.13531

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