Abstract:
For mixed type equation in a rectangle, we study boundary-value problems with nonlocal boundary condition that connects the values of the sought-for solution and its derivative along the normal at upper and lower bases of the rectangle which belong to different types of studied equation. By the method of spectral analysis we establish criteria of uniqueness of solutions that are constructed in the form of the sum of the Fourier series. We establish the stability of solutions for a nonlocal condition.
Keywords:equation of mixed type, spectral method, existence, uniqueness, stability.