In this paper, we study the problem of simultaneous approximation to biva-riate function by one variate function, i.e., minimizing the expression(?) over G, G is an noempty subset in C(X) .We obtain the qharacterization theorems, the uniqueness theorems, the strong uniqueness theorems and de la Vallée Poussin theorems. We also establish the first algorithm of Remes type and two limit theorems . |