Difference between revisions of "Vector space"
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* if <math>x \in V</math>, <math>1.{\mathbf x}={\mathbf x}</math> | * if <math>x \in V</math>, <math>1.{\mathbf x}={\mathbf x}</math> | ||
| − | === | + | == Subspaces == |
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| + | If <math>S \subseteq V</math>, and <math>\mathbf S</math> is a vector space itself, then it is called a subspace of | ||
| + | <math>\mathbf V</math>. | ||
Revision as of 13:31, 4 November 2006
This article is a stub. Help us out by expanding it.
A vector space over a field (frequently the real numbers) is an object which arises in linear algebra and abstract algebra. A vector space 
over a field 
consists of a set (of vectors) and two operations, vector addition and scalar multiplication, which obey the following rules:
Axioms of a vector space
- Under vector addition, the set of vectors forms an abelian group. Thus, addition is associative and commutative and there is an additive identity (usually denoted
) and additive inverses.
) and additive - Scalar multiplication is associative, so if
and 
then 
.
and 
then 
.- Scalar multiplication is distributive over both vector and scalar addition, so if
and 
then 
.
and 
then 
.- if
, 
, 
Subspaces
If 
, and 
is a vector space itself, then it is called a subspace of
.
