Abstract
Let A be a positive bounded linear operator acting on a complex Hilbert space \({\mathcal {H}}\). Our aim in this paper is to prove some A-numerical radius inequalities of bounded linear operators acting on \({\mathcal {H}}\) when an additional semi-inner product structure induced by A is considered. In particular, an alternative proof of a recent result proved in Moslehian et al. (Linear Algebra Appl 591:299–321 2020) is given.
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The author would like to thank the referee for his/her valuable comments, which helped to improve the exposition.
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Feki, K. A note on the A-numerical radius of operators in semi-Hilbert spaces. Arch. Math. 115, 535–544 (2020). https://doi.org/10.1007/s00013-020-01482-z
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DOI: https://doi.org/10.1007/s00013-020-01482-z