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Yamazaki, T. (2007) On Upper and Lower Bounds of the Numerical Radius and an Equality Condition. Studia Mathematica, 178, 83-89.
https://doi.org/10.4064/sm178-1-5

has been cited by the following article:

• TITLE: Numerical Radius Inequalities for Sums and Products of Operators

  AUTHORS: Wasim Audeh

  KEYWORDS: Numeriacl Radius, Operator Norm, Operator Matrix, Inequality, Equality, Offdiagonal Part

  JOURNAL NAME: Advances in Linear Algebra & Matrix Theory, Vol.9 No.3, July 10, 2019

  ABSTRACT: A numerical radius inequality due to Shebrawi and Albadawi says that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then for all r≥1. We give sharper numerical radius inequality which states that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then where . Moreover, we give many numerical radius inequalities which are sharper than related inequalities proved recently, and several applications are given.