Multipoint boundary-value problems with pulse effects

By using pseudoinverse matrices, we establish conditions for the existence and uniqueness of solutions of linear and weakly linear boundary-value problems for ordinary differential equations with pulse action. We consider the case where the dimension of a differential system does not coincide with the dimension of the boundary conditions.Published in Ukrainskii Matematicheskii Zhurnal, Vol. 47, No. 6, pp. 770–774, June, 1995.