Geometric properties of inverse polynomial images

Klaus Schiefermayr

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arXiv · 1306.5872

Geometric properties of inverse polynomial images

Klaus Schiefermayr

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Abstract

Given a polynomial $\T_n$ of degree $n$, consider the inverse image of $\R$ and $[-1,1]$, denoted by $\T_n^{-1}(\R)$ and $\T_n^{-1}([-1,1])$, respectively. It is well known that $\T_n^{-1}(\R)$ consists of $n$ analytic Jordan arcs moving from $\infty$ to $\infty$. In this paper, we give a necessary and sufficient condition such that (1) $\T_n^{-1}([-1,1])$ consists of $\nu$ analytic Jordan arcs and (2) $\T_n^{-1}([-1,1])$ is connected, respectively.

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Klaus Schiefermayr. 2013-06-25. Geometric properties of inverse polynomial images. https://arxiv.org/abs/1306.5872

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