Line 1: Line 1:
 
[[Category: MA351]]
 
[[Category: MA351]]
 +
[[Category:linear algebra]]
 +
 
=Rank Nullity Theorem=
 
=Rank Nullity Theorem=
 
In its most basic form, the rank nullity theorem states that for the [[Linear_transformation|linear transformation]] T represented by the m by n matrix A, then <math>\text{rank}(A)+\text{nullity}(A)=m</math>.  Where rank is the number of rows in A with leading ones and nullity is the number of rows without leading ones.  Nullity also happens to be the dimension of the [[Kernel_(linear_algebra)|kernel]] of A and the rank is the dimension of the [[Image_(linear_algebra)|image]] of A.  Therefore the rank nullity theorem can be re-written as <math>\text{dim}(\text{im}(A))+\text{dim}(\text{ker}(A))=m</math> where <math>\text{im}(A)</math> is the [[Image_(linear_algebra)|image of the matrix]] A, and <math>\text{ker}(A)</math> is the [[Kernel_(linear_algebra)|kernel of the matrix]]  A.
 
In its most basic form, the rank nullity theorem states that for the [[Linear_transformation|linear transformation]] T represented by the m by n matrix A, then <math>\text{rank}(A)+\text{nullity}(A)=m</math>.  Where rank is the number of rows in A with leading ones and nullity is the number of rows without leading ones.  Nullity also happens to be the dimension of the [[Kernel_(linear_algebra)|kernel]] of A and the rank is the dimension of the [[Image_(linear_algebra)|image]] of A.  Therefore the rank nullity theorem can be re-written as <math>\text{dim}(\text{im}(A))+\text{dim}(\text{ker}(A))=m</math> where <math>\text{im}(A)</math> is the [[Image_(linear_algebra)|image of the matrix]] A, and <math>\text{ker}(A)</math> is the [[Kernel_(linear_algebra)|kernel of the matrix]]  A.
Line 5: Line 7:
 
*I think that it should be "n by m" matrix, meaning that rank(A) + nullity(A)= m (number of columns, not rows as it states here)!!  
 
*I think that it should be "n by m" matrix, meaning that rank(A) + nullity(A)= m (number of columns, not rows as it states here)!!  
 
----
 
----
[[Linear_Algebra_Resource|Back to Linear Algebra Resource]]
+
[[Linear_Algebra_Resource|Back to "Important Concepts in Linear Algebra"]]
  
 
[[MA351|Back to MA351]]
 
[[MA351|Back to MA351]]

Latest revision as of 09:46, 20 May 2013


Rank Nullity Theorem

In its most basic form, the rank nullity theorem states that for the linear transformation T represented by the m by n matrix A, then $ \text{rank}(A)+\text{nullity}(A)=m $. Where rank is the number of rows in A with leading ones and nullity is the number of rows without leading ones. Nullity also happens to be the dimension of the kernel of A and the rank is the dimension of the image of A. Therefore the rank nullity theorem can be re-written as $ \text{dim}(\text{im}(A))+\text{dim}(\text{ker}(A))=m $ where $ \text{im}(A) $ is the image of the matrix A, and $ \text{ker}(A) $ is the kernel of the matrix A.

  • I think that it should be "n by m" matrix, meaning that rank(A) + nullity(A)= m (number of columns, not rows as it states here)!!

Back to "Important Concepts in Linear Algebra"

Back to MA351

Alumni Liaison

Sees the importance of signal filtering in medical imaging

Dhruv Lamba, BSEE2010