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arXiv · 2001.09706

Estimations of zeros of a polynomial using numerical radius inequalities

Pintu Bhunia·Santanu Bag·Raj Kumar Nayak·Kallol Paul
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Abstract

We present new bounds for the numerical radius of bounded linear operators and $2\times 2$ operator matrices. We apply upper bounds for the numerical radius to the Frobenius companion matrix of a complex monic polynomial to obtain new estimations for zeros of that polynomial. We also show with numerical examples that our new estimations improve on the existing estimations.

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Pintu Bhunia, Santanu Bag, Raj Kumar Nayak, Kallol Paul. 2020-01-27. Estimations of zeros of a polynomial using numerical radius inequalities. https://arxiv.org/abs/2001.09706

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