Difference between revisions of "Span"

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(Created page with "==Definition== Given a set of vectors {{M|S}} in a vector space {{M|(V,F)}} the '''span'''<ref>Advanced Linear Algebra - Roman - Springer GTM (CHECK THIS REF)...")
 
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* <math>\text{Span}(\{v_1,\cdots,v_m\})=\left\{\lambda_1v_1+\cdots+\lambda_mv_m|\ \lambda_i\in F\right\}</math><math>=\left\{\sum^m_{i=1}\lambda_iv_i\Big|\ \lambda_i\in F\right\}</math>
 
* <math>\text{Span}(\{v_1,\cdots,v_m\})=\left\{\lambda_1v_1+\cdots+\lambda_mv_m|\ \lambda_i\in F\right\}</math><math>=\left\{\sum^m_{i=1}\lambda_iv_i\Big|\ \lambda_i\in F\right\}</math>
  
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==Immediate theorems==
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{{Begin Theorem}}
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The span is [[Subspace#Vector space|vector subspace]] of {{M|V}}
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{{Begin Proof}}
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{{Todo|Proof}}
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{{End Proof}}{{End Theorem}}
  
 
==References==
 
==References==
 
<references/>
 
<references/>
 
{{Definition|Linear Algebra}}
 
{{Definition|Linear Algebra}}

Latest revision as of 17:09, 28 May 2015

Definition

Given a set of vectors [ilmath]S[/ilmath] in a vector space [ilmath](V,F)[/ilmath] the span[1] is defined as follows:

  • [math]\text{Span}(S)=\left\{\sum^n_{i=1}\lambda v_i\Big|\ n\in\mathbb{N},\ v_i\in S,\ \lambda_i\in F\right\}[/math]

It is very important that only finite linear combinations are in the span.

Span of a finite set of vectors

Given a finite set [ilmath]\{v_1,\cdots,v_m\} [/ilmath] of vectors the span[2] can be more simply written:

  • [math]\text{Span}(\{v_1,\cdots,v_m\})=\left\{\lambda_1v_1+\cdots+\lambda_mv_m|\ \lambda_i\in F\right\}[/math][math]=\left\{\sum^m_{i=1}\lambda_iv_i\Big|\ \lambda_i\in F\right\}[/math]

Immediate theorems

The span is vector subspace of [ilmath]V[/ilmath]




TODO: Proof



References

  1. Advanced Linear Algebra - Roman - Springer GTM (CHECK THIS REF)
  2. Linear Algebra via Exterior Products - Sergei Winitzki