مقال بحثي وصول مفتوح
Finite Dimensional Chebyshev Subspaces of Lo
If A is a subset of the normed linear space X, then A is said to be proximinal in X if for each xÎX there is a point y0ÎA such that the distance between x and A; d(x, A) = inf{||x-y||: yÎA}= ||x-y0||. The element y0 is called a best approximation for x from A. If for each xÎX, the best approximation for x from A is un …