On some properties of determinants with complex elements and their practical application

Fìz.-mat. model. ìnf. tehnol. 2021, 31:67-77

Abstract

The formulas presented in this paper make it possible to select the real and imaginary part of the determinant value of the n -th order complex quantity, greatly simplifying the process of its deployment. Moreover, its module is given by the determinant of the 2n -th order, the elements of which are the real and imaginary parts of complex numbers. This makes it possible to analyze analytically the process described using determinants with complex numbers. The real and imaginary parts are also determined by the sum of determinants already with n rows and columns, the elements of which make up complex elements. The terms of this sum are solutions of a system of equations represented in closed form using symmetric polynomials, the arguments of which are its coefficients. Part of this combination is expressed by two determinants of the n -th order, the elements of which are the sum and difference of the real and imaginary parts of the elements. This significantly reduces the number of arithmetic operations during the deployment of a complex determinant and the selection of its real and imaginary parts. The given numerical example confirms the feasibility of this approach.

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