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arXiv · 1903.06857

Numerical radius inequalities of operator matrices with applications

Pintu Bhunia·Santanu Bag·Kallol Paul
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Abstract

We present upper and lower bounds for the numerical radius of $2 \times 2$ operator matrices which improves on the existing bound for the same. As an application of the results obtained we give a better estimation for the zeros of a polynomial.

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Pintu Bhunia, Santanu Bag, Kallol Paul. 2019-03-16. Numerical radius inequalities of operator matrices with applications. https://doi.org/10.1080/03081087.2019.1634673

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