Usual, quadratic and cubic numerical ranges corresponding to a $3\times 3$ operator matrices

Authors

Mubina Sharipova, Bukhara State University, Bukhara, UzbekistanFollow

Abstract

In the present paper we consider bounded self-adjoint 3x3 operator matrices A. An alternative formula for the calculating the cubic numerical range of the operator matrices A is derived. The components of the quadratic numerical range with respect to the expansion of the Hilbert space are found.

First Page

242

Last Page

249

References

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Recommended Citation

Sharipova, Mubina (2022) "Usual, quadratic and cubic numerical ranges corresponding to a $3\times 3$ operator matrices," Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences: Vol. 5: Iss. 4, Article 3.
DOI: https://doi.org/10.56017/2181-1318.1236