Korean Journal of Mathematics

The Kangwon-Kyungki Mathematical Society (강원경기수학회)
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ON NUMERICAL RANGE AND NUMERICAL RADIUS OF CONVEX FUNCTION OPERATORS

  • Zaiz, Khaoula (Department of Mathematics Operators Theory and PDE Foundations and Applications Lab University of El-Oued) ;
  • Mansour, Abdelouahab (Department of Mathematics Operators Theory and PDE Foundations and Applications Lab University of El-Oued)
  • Received : 2019.04.07
  • Accepted : 2019.09.21
  • Published : 2019.12.30
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Abstract

In this paper we prove some interesting inclusions concerning the numerical range of some operators and the numerical range of theirs ranges with a convex function. Further, we prove some inequalities for the numerical radius. These inclusions and inequalities are based on some classical convexity inequalities for non-negative real numbers and some operator inequalities.

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References

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