On the error of the interpolation by bilinear splines

We study the problem of approximation of functions from the classes W^r,s H and W^r,s H ^,2by bilinear splines. For some values ofr ands, we obtain exact estimates of the error.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 11, pp. 1554–1560, November, 1994.