Let K(X,Y) be the space of compact operators. For a proximinal subspace Z⊂Y, this paper deals with question, when does every Y-valued operator admit Z-valued best approximation? any reflexive Banach X and for L1-predual Y, if Z⊂Y is strongly finite codimension, we show that K(X,Z) under an additional condition on position K(X,Z). When Y c0-direct sum dimensional spaces achieve strong transitivi...

Lasserre [32] proved that for every compact set K⊂Rn and even number d there exists a unique homogeneous polynomial g0 of degree with K⊂G1(g0)={x∈Rn:g0(x)≤1} minimizing |G1(g)| among all such polynomials g fulfilling the condition K⊂G1(g). This result extends notion Löwner ellipsoid, not only from convex bodies to arbitrary sets (which was immediate if d=2 by taking hulls), but also ellipsoids ...

We study the theory of best approximation in tensor product and the direct sum of some lattice normed spacesX_{i}. We introduce quasi tensor product space anddiscuss about the relation between tensor product space and thisnew space which we denote it by X boxtimesY. We investigate best approximation in direct sum of lattice normed spaces by elements which are not necessarily downwardor upward a...

in this paper, using the best proximity theorems for an extensionof brosowski's theorem. we obtain other results on farthest points. finally, wedene the concept of e- farthest points. we shall prove interesting relationshipbetween the -best approximation and the e-farthest points in normed linearspaces (x; ||.||). if z in w is a e-farthest point from an x in x, then z is also a-best ...