BEST APPROXIMATION HAVING RESTRICTED RANGES WITH NODES
具有结点的约束值域的最佳逼近

In this paper we discuss the problem of best approximation having restrictedranges, while the restricted functions may be arbitrary discontinuous ones, and may take thesame values at some nodes, namely d(l, u) = 0 and establish in the Chebyshev sense thecorresponding theorems including the alternation theorem.