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arXiv · 1903.03403

Numerical radius inequalities and its applications in estimation of zeros of polynomials

Pintu Bhunia·Santanu Bag·Kallol Paul
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Abstract

We present some upper and lower bounds for the numerical radius of a bounded linear operator defined on complex Hilbert space, which improves on the existing upper and lower bounds. We also present an upper bound for the spectral radius of sum of product of $n$ pairs of operators. As an application of the results obtained, we provide a better estimation for the zeros of a given polynomial.

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Pintu Bhunia, Santanu Bag, Kallol Paul. 2019-03-08. Numerical radius inequalities and its applications in estimation of zeros of polynomials. https://doi.org/10.1016/j.laa.2019.03.017

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