About three-dimensional analogue of the problem of Tricomi with parallel planes of extinction

Three-dimensional analogue of the problem of Tricomi with non-characteristic parallel planes of change of types of the equation is investigated for a parabolic-hyperbolic equation. The uniqueness of the solution of the problem is proved by the method of a priori estimates, and the existence of the solution of the problem is enlightened to the existence of a solution of the system of the second type Voltaire integral equation.