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Refined and generalized numerical radius inequalities for \(2 \times 2\) operator matrices. (English) Zbl 1466.15017

Summary: We give several refined and generalized numerical radius inequalities for \(2\times 2\) operator matrices. These inequalities improve and generalize earlier related inequalities. An application of some of our results is also given.

MSC:

15A45 Miscellaneous inequalities involving matrices
15A60 Norms of matrices, numerical range, applications of functional analysis to matrix theory
47A12 Numerical range, numerical radius
47A30 Norms (inequalities, more than one norm, etc.) of linear operators
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