Best Co-approximation and Worst Approximation by Closed Unit Balls
Subject Areas : Mathematical Analysis
1 - Department of Mathematics, Yazd University, Yazd, Iran
Keywords: Copoximinal, Closed Unit Balls, Qcoproximinal, Uniquely remotal, Cochebyshevl,
Abstract :
A kind of approximation, called best coapproximation was introduced and discussed in normed linear spaces by C. Franchetti and M. Furi in 1972. Subsequently, this study was taken up by several researchers in different abstract spaces. In this paper, we consider best coapproximation by closed unit balls. We define qcoproximinal and coremotal, and find some theorems.