BOUNDARY VALUE PROBLEM FOR HYPERBOLIC INTEGRO-DIFFERENTIAL EQUATIONS OF MIXED TYPE

The boundary value problem for a system of hyperbolic integro-differential equations ofmixed type with degenerate kernels is considered on a rectangular domain. This problem is reducedto a family of boundary value problems for a system of integro-differential equations of mixed typeand integral relations. The system of integro-differential equations of mixed type is transferred to asystem of Fredholm integro-differential equations. For solving the family of boundary value problemsfor integro-differential equations Dzhumabaev’s parametrization method is applied. A new conceptof a general solution to a system of integro-differential equations with parameter is developed. Thedomain is divided into N subdomains by a temporary variable, the values of a solution at the interiorlines of the subdomains are considered as additional functional parameters, and a system ofintegro-differential equations is reduced to a family of special Cauchy problems on the subdomains forFredholm integro-differential equation with functional parameters. Using the solutions to these problems,a new general solutions to a system of Fredholm integro-differential equations with parameteris introduced and its properties are established. Based on a general solution, boundary conditions,and the continuity conditions of a solution at the interior lines of the partition, a system of linearfunctional equations with respect to parameters is composed. Its coefficients and right-hand sidesare found by solving the family of special Cauchy problems for Fredholm integro-differential equationson the subdomains. It is shown that the solvability of the family of boundary value problemsfor Fredholm integro-differential equations is equivalent to the solvability of the composed system.Methods for solving boundary value problems are proposed, which are based on the construction andsolving of these systems. Conditions for the existence and uniqueness of a solution to the boundaryvalue problem for a system of hyperbolic integro-differential equations of mixed type with degeneratekernels are obtained.