Bounded set: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Hendra I. Nurdin
(Start on bounded set)
 
imported>Hendra I. Nurdin
m (typo)
Line 1: Line 1:
In [[mathematics]], a '''bounded set''' is any [[set|subset]] of a [[normed space]] whose elements all have norms which are bounded from above by a fixed positive real constant. In other words, all its elements are uniformly bounded in magnitude.
In [[mathematics]], a '''bounded set''' is any [[set|subset]] of a [[normed space]] whose elements all have norms which are bounded from above by a fixed positive real constant. In other words, all its elements are uniformly bounded in magnitude.


==Formal Definition==
==Formal definition==
Let ''X'' be a normed space with the [[norm]] <math>\|\cdot\|</math>. Then a set <math>A \subset X</math> is bounded if there exists a real number ''M>0'' such that <math>\|x\|\leq M</math> for all <math>x \in A</math>.
Let ''X'' be a normed space with the [[norm]] <math>\|\cdot\|</math>. Then a set <math>A \subset X</math> is bounded if there exists a real number ''M>0'' such that <math>\|x\|\leq M</math> for all <math>x \in A</math>.



Revision as of 18:47, 28 September 2007

In mathematics, a bounded set is any subset of a normed space whose elements all have norms which are bounded from above by a fixed positive real constant. In other words, all its elements are uniformly bounded in magnitude.

Formal definition

Let X be a normed space with the norm . Then a set is bounded if there exists a real number M>0 such that for all .