Abstract
The most important problems of the spectral theory include the determination of the defect index of a differential operator as a function of the behavior of the coefficients of the differential expression. The main task of the spectral theory of differential operators is the characteristic of the spectrum of the operator also depending on the behavior of the coefficients of the differential expression generating the operator. In this paper we study the dependence of the spectrum on the behavior of the coefficients of the corresponding differential expression. The asymptotic behavior of the eigenvalues and eigen functions of a differential operator is studied, some information is obtained on the characteristic of the behavior of eigenvalues that are of interest in the theory of differential operators.
Keywords
Eigenvalues, behavior of coefficients, spectral theory, differential operator.
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