Far Eastern Mathematical Journal

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Distortion theorem for polynomials with real critical points

Dubinin V.N.

2025, issue 2, P. 258–260 DOI: https://doi.org/10.47910/FEMJ202519

Abstract

For polynomials f with real critical points, a lower bound of f'(z) is considered, which depends on the two critical points \zeta_1, \zeta_2 of the polynomial f closest to z, \zeta_1<z<\zeta_2, the values f(z), f(\zeta_k), k=1,2, and is independent of the degree of the polynomial f.

Keywords: polynomials, critical points, critical values, distortion theorem.

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References

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