Abstract:
On a finite closed interval, we obtain the asymptotics of the eigenvalues of a differential operator of order $2m$ perturbed by a differential operator of order $2m-2$ given by a quasidifferential expression. We also consider the case of multiple eigenvalues.
Keywords:perturbation of a differential operator, spectrum of perturbations, quasidifferential expression, Hilbert space, Dirichlet boundary conditions, resolvent of an operator.