In this article, we considered bidual spaces and reflexivity of real normed spaces. At first we proved some corollaries applying Hahn-Banach theorem and showed related theorems. In the second section, we proved the norm of dual spaces and defined the natural mapping, from real normed spaces to bidual spaces. We also proved some properties of this mapping. Next, we defined real normed space of R...

The Hahn-Banach theorem in its simplest form asserts that a bounded linear functional defined on a subspace of a Banach space can be extended to a linear functional defined everywhere, without increasing its norm. There is an order-theoretic version of this extension theorem (Theorem 0.1 below) that is often more useful in context. The purpose of these lecture notes is to discuss the noncommuta...

For a new class of topological vector spaces, namely κ-normed spaces, an associated quasisemilinear topological preordered space is defined and investigated. This structure arise naturally from the consideration of a κ-norm, that is a distance function between a point and a G δ-subset. For it, analogs of the Hahn-Banach theorem are proved.

The concept of b-linear functional and its different types continuity in linear n-normed space are presented some their properties being established. We derive the Uniform Boundedness Principle Hahn-Banach extension Theorem with help bounded functionals case spaces discuss examples applications. Finally, we present weak*convergence for sequence space.

In this article, we considered bidual spaces and reflexivity of real normed spaces. At first we proved some corollaries applying Hahn-Banach theorem and showed related theorems. In the second section, we proved the norm of dual spaces and defined the natural mapping, from real normed spaces to bidual spaces. We also proved some properties of this mapping. Next, we defined real normed space of R...

This article contains the Hahn Banach theorem in the vector space over the field of complex numbers. provide the terminology and notation for this paper. The following propositions are true: (1) For every element z of C holds ||z|| = |z|. (2) For all elements x 1 , y 1 , x 2 , y 2 of R holds (x 1 + y 1 i) · (x 2 + y 2 i) = (x 1 · x 2 − y 1 · y 2) + (x 1 · y 2 + x 2 · y 1)i. (3) For every real n...

The present review paper provides recent results on convexity and its applications to the constrained extension of linear operators, motivated by existence subgradients continuous convex Markov moment problem related approximation using Krein–Milman theorem, optimization, polynomial unbounded subsets. In many cases, Mazur–Orlicz theorem also leads operators as solutions. common point all these ...

We introduce max-plus analogues of basic Euclidian geometry notions: scalar product is replaced by a scalar division, and the associated distance is essentially Hilbert’s projective distance. We introduce an orthogonal projection and prove a Hahn-Banach type theorem: a point can be separated from a semimodule by a hyperplane orthogonal to the direction of projection. We use these results to sep...