ON BASES IN BANACH SPACES

Abstract

A direct expansion of a Banach space with respect to subspaces is considered. A method for
constructing a basis for a space proceeding from bases for subspaces is offered. We also consider
the cases when the bases for subspaces are isomorphic and the corresponding isomorphisms may
not hold. And we study the completeness and the minimality of corresponding systems.
Keywords: basis, completeness, minimality