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<u>'''Linear Independence'''</u>  
 
<u>'''Linear Independence'''</u>  
  
If det(vectors)&nbsp;!= 0 ⇔ '''linearly independent'''<br>  
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If det(vectors)&nbsp;!= 0 ⇔ '''linearly independent'''<br> If end result of the rref(vectors) gives you a matrix with all rows having leading 1's it is '''linearly independent'''.
  
If det(vectors) = 0 ⇔ '''linearly dependent'''<br>If end result of the rref(vectors) is in the order of [0 0 0 0] and provided the system is consistent, the vectors are '''linearly dependent.'''  
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If det(vectors) = 0 ⇔ '''linearly dependent'''<br>If end result of the rref(vectors) gives you a parameter in the equation, the vectors are '''linearly dependent.'''  
  
 
Tip: If #No of vectors &gt; Dimension ⇔ it is '''linearly dependent'''<br>  
 
Tip: If #No of vectors &gt; Dimension ⇔ it is '''linearly dependent'''<br>  

Revision as of 08:18, 1 May 2011

Tricks for checking Linear Independence, Span and Basis



Linear Independence

If det(vectors) != 0 ⇔ linearly independent
If end result of the rref(vectors) gives you a matrix with all rows having leading 1's it is linearly independent.

If det(vectors) = 0 ⇔ linearly dependent
If end result of the rref(vectors) gives you a parameter in the equation, the vectors are linearly dependent.

Tip: If #No of vectors > Dimension ⇔ it is linearly dependent

Span

If Dimension > #No of vectors -> it CANNOT span

If det(vectors) != 0 ⇔ it spans
If end result of the rref(vectors) gives you a matrix with all rows having leading 1's, it spans.

If det(vectors) = 0 ⇔ does not span
If end result of the rref(vectors) gives you a matrix with not all rows having a leading 1, it does not span. Basis


If Dimension > #No of vectors ⇔ cannot span ⇔ is not a basis

If #No of vectors > Dimension -> it has to be linearly dependent to span (check the tip)

If #No of vectors = Dimension -> it has to be linearly independent to span

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Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett