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arXiv · 0912.1030

Zeros of 2 by 2 Matrix Polynomials

Marla Slusky
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Abstract

Consider the $n$th degree polynomial equation, $X^n+A_{n-1}X^{n-1}+...+A_1X+A_0=0$ over the ring of 2 by 2 complex matrices. If this equation has more than ${2n \choose 2}$ solutions, then it has infinitely many solutions. We show here that for any $n,m \in\N$ such that $m\leq{2n \choose 2}$, there exists an $n$th degree polynomial equation with exactly $m$ solutions.

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Marla Slusky. 2009-12-05. Zeros of 2 by 2 Matrix Polynomials. https://arxiv.org/abs/0912.1030

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