Differentiation of resultants and common roots of pairs of polynomials

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Chernyavsky, Mikhail, Lebedev, Andrei, Trubnikov, Yurii
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866909167872114688
author Chernyavsky, Mikhail
Lebedev, Andrei
Trubnikov, Yurii
author_facet Chernyavsky, Mikhail
Lebedev, Andrei
Trubnikov, Yurii
contents The well-known mathematical instrument for detection common roots for pairs of polynomials and multiple roots of polynomials are resultants and discriminants. For a pair of polynomials $f$ and $g$ their resultant $R(f,g)$ is a function of their coefficients. Zeros of resultant $R(f,g)$ correspond to the families of coefficients of $f$ and $g$ such that $f$ and $g$ have a common root. Herewith the calculation of this common root is a separate problem. The principal results on calculation of a unique common root of two polynomials and also about calculating a unique root of multiplicity 2 of a polynomial in terms of the first order partial derivatives of resultants and discriminants are given in the monograph by I.M. Gelfand, M.M. Kapranov, A.V. Zelevinsky [1, Ch. 3, Ch. 12]. A significant development of the ideas of this book in the direction of searching for formulas for multiple roots of polynomials is presented in the paper by I.A. Antipova, E.N. Mikhalkin, A.K. Tsikh [2]. The key result of this article is [2, Theorem 1] where the expression for a unique root of multiplicity $s \geq 3$ in terms of the first order partial derivatives of resultant of the polynomial and it's derivative of order $s-1$. In the present article the explicit formulas for higher derivatives of resultants of pairs of polynomials possessing common roots are obtained. On this basis a series of results that differ in ideas from [2, Theorem 1] linking higher derivatives of resultants and common multiple roots are proven. In addition the results obtained are applied for a new transparent proof of a refinement of [2, Theorem 1].
format Preprint
id arxiv_https___arxiv_org_abs_2404_08550
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Differentiation of resultants and common roots of pairs of polynomials
Chernyavsky, Mikhail
Lebedev, Andrei
Trubnikov, Yurii
Classical Analysis and ODEs
Functional Analysis
30C15, 12D10, 15A15, 13P15
The well-known mathematical instrument for detection common roots for pairs of polynomials and multiple roots of polynomials are resultants and discriminants. For a pair of polynomials $f$ and $g$ their resultant $R(f,g)$ is a function of their coefficients. Zeros of resultant $R(f,g)$ correspond to the families of coefficients of $f$ and $g$ such that $f$ and $g$ have a common root. Herewith the calculation of this common root is a separate problem. The principal results on calculation of a unique common root of two polynomials and also about calculating a unique root of multiplicity 2 of a polynomial in terms of the first order partial derivatives of resultants and discriminants are given in the monograph by I.M. Gelfand, M.M. Kapranov, A.V. Zelevinsky [1, Ch. 3, Ch. 12]. A significant development of the ideas of this book in the direction of searching for formulas for multiple roots of polynomials is presented in the paper by I.A. Antipova, E.N. Mikhalkin, A.K. Tsikh [2]. The key result of this article is [2, Theorem 1] where the expression for a unique root of multiplicity $s \geq 3$ in terms of the first order partial derivatives of resultant of the polynomial and it's derivative of order $s-1$. In the present article the explicit formulas for higher derivatives of resultants of pairs of polynomials possessing common roots are obtained. On this basis a series of results that differ in ideas from [2, Theorem 1] linking higher derivatives of resultants and common multiple roots are proven. In addition the results obtained are applied for a new transparent proof of a refinement of [2, Theorem 1].
title Differentiation of resultants and common roots of pairs of polynomials
topic Classical Analysis and ODEs
Functional Analysis
30C15, 12D10, 15A15, 13P15
url https://arxiv.org/abs/2404.08550