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On conjugate points of solutions of non-selfadjoint differential systems. (English) Zbl 0664.34045
Oscillation properties of the linear differential system (1) $$y'=B(x)z$$, $$z'=C(x)y$$, where B,C are $$n\times n$$ matrices of real-valued functions, are investigated. The principal method used in the paper consists in the transformation of (1) into the so called generalized trigonometric system (2) $$S'=Q(x)C$$, $$C'Q^ T(x)S$$, where Q(x) is an $$n\times n$$ matrix of real valued functions. This method enables to study oscillation properties of (1) by means of oscillation behaviour of certain self- adjoint system of double dimension.
Reviewer: O.Došlý
##### MSC:
 34C10 Oscillation theory, zeros, disconjugacy and comparison theory for ordinary differential equations
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##### References:
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