Angles in metric and normed linear spaces
نویسندگان
چکیده
منابع مشابه
A Metric Characterization of Normed Linear Spaces
Let X be a linear space over a field K = R or C, equipped with a metric ρ. It is proved that ρ is induced by a norm provided it is translation invariant, real scalar “separately” continuous, such that every 1-dimensional subspace of X is isometric to K in its natural metric, and (in the complex case) ρ(x, y) = ρ(ix, iy) for any x, y ∈ X.
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ژورنال
عنوان ژورنال: Colloquium Mathematicum
سال: 1976
ISSN: 0010-1354,1730-6302
DOI: 10.4064/cm-34-2-209-217