Best Approximation in TVS

Document Type: Research articles

Authors

Faculty of Mathematics, Ayatollah Boroujerdi University, Boroujerd, Iran

Abstract

In this paper  we give new
results on the best approximation  in the Hausdorff topological vector
space and  consider relationship  with orthogonality. Also we determined under  what
 conditions the map $P_{K,f}$ is upper semicontinous.