{ "id": "1904.10694", "version": "v1", "published": "2019-04-24T08:38:10.000Z", "updated": "2019-04-24T08:38:10.000Z", "title": "Descartes' rule of signs and moduli of roots", "authors": [ "Vladimir Petrov Kostov" ], "categories": [ "math.CA" ], "abstract": "A hyperbolic polynomial (HP) is a real univariate polynomial with all roots real. By Descartes' rule of signs a HP with all coefficients nonvanishing has exactly $c$ positive and exactly $p$ negative roots counted with multiplicity, where $c$ and $p$ are the numbers of sign changes and sign preservations in the sequence of its coefficients. For $c=1$ and $2$, we discuss the question: When the moduli of all the roots of a HP are arranged in the increasing order on the real half-line, at which positions can be the moduli of its positive roots depending on the positions of the sign changes in the sequence of coefficients?", "revisions": [ { "version": "v1", "updated": "2019-04-24T08:38:10.000Z" } ], "analyses": { "keywords": [ "sign changes", "real univariate polynomial", "coefficients", "hyperbolic polynomial", "sign preservations" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }