Spectral properties of solutions of a non-local problem for the mixed type equation with non-smooth lines of changing type

摘要

In the article, a uniqueness theorem is proved for the solution of a spectral non-local problem for the mixed type equation with two lines of changing type. In the case when the uniqueness theorem does not hold, eigenvalues and eigenfunctions are found. For this problem, completeness of the system of eigenfunctions is proved.