Document Type: Research Paper

**Author**

Department of Mathematics,Marand Branch, Islamic azad university, Marand, Iran.

**Abstract**

Fuzzy best simultaneous approximation of a finite number of functions is considered. For this purpose, a fuzzy norm on $C\left (X, Y \right )$ and its fuzzy dual space and also the set of subgradients of a fuzzy norm are introduced. Necessary case of a proved theorem about characterization of simultaneous approximation will be extended to the fuzzy case.

**Keywords**

**Main Subjects**

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