• Silvestru Sever Dragomir
Part of the SpringerBriefs in Mathematics book series (BRIEFSMATH)


In this introductory chapter we present some fundamental facts about the numerical range and the numerical radius of bounded linear operators in Hilbert spaces that are used throughout the book. Some famous inequalities due to Berger, Holbrook, Fong and Holbrook and Bouldin are given. More recent results obtained by Kittaneh, El-Haddad and Kittanek and Yamazaki are provided as well.


Numerical Radius Kittaneh Numerical Range Fundamental Fact Introductory Chapter 
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Copyright information

© Silvestru Sever Dragomir 2013

Authors and Affiliations

  • Silvestru Sever Dragomir
    • 1
    • 2
  1. 1.College of Engineering and ScienceVictoria UniversityMelbourneAustralia
  2. 2.School of Computational and Applied MathematicsUniversity of the Withwatersrand BraamfonteinJohannesburgSouth Africa

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