Approximate method for solving an elliptic problem with discontinuous coefficients (Q1334858)

The author develops the method proposed in his earlier work [\textit{Dang Quang A}, Application of extrapolation to constructing effective method for solving the Dirichlet problem for biharmonic equation, Preprint No. 5, Inst. Comput. Sci., Hanoi (1990)]. He constructs the approximate solution of the problem considered by \textit{V. G. Osmolovskij} and \textit{V. Ya. Rivkind} [Zh. Vychisl. Mat. Mat. Fiz. 21, 35-39 (1981; Zbl 0491.65056)] with the convergence rate of geometric progression. The method is based on extrapolation of solutions for problems which contain a small parameter in the boundary condition.