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arXiv · 1906.07363

Bounds for zeros of a polynomial using numerical radius of Hilbertian space operators

Pintu Bhunia·Santanu Bag·Kallol Paul
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Abstract

We obtain bounds for the numerical radius of $2 \times 2$ operator matrices which improve on the existing bounds. We also show that the inequalities obtained here generalize the existing ones. As an application of the results obtained here we estimate the bounds for the zeros of a monic polynomial and illustrate with numerical examples that the bounds are better than the existing ones.

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Pintu Bhunia, Santanu Bag, Kallol Paul. 2019-06-18. Bounds for zeros of a polynomial using numerical radius of Hilbertian space operators. https://doi.org/10.1007/s43034-020-00107-4

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