Difference between revisions of "031 Review Part 2, Problem 9"

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<span class="exam">Consider the matrix &nbsp;<math style="vertical-align: -31px">A=   
+
<span class="exam">If &nbsp;<math style="vertical-align: 0px">A</math>&nbsp; is an &nbsp;<math style="vertical-align: 0px">n\times n</math>&nbsp; matrix such that &nbsp;<math style="vertical-align: -4px">AA^T=I,</math>&nbsp; what are the possible values of &nbsp;<math style="vertical-align: 0px">\text{det }A?</math>
    \begin{bmatrix}
 
          1 & -4 & 9 & -7 \\
 
          -1 & 2  & -4 & 1 \\
 
          5 & -6 & 10 & 7
 
        \end{bmatrix}</math>&nbsp; and assume that it is row equivalent to the matrix
 
 
 
::<math>B=   
 
    \begin{bmatrix}
 
          1 & 0 & -1 & 5 \\
 
          0 & -2  & 5 & -6 \\
 
          0 & 0 & 0 & 0
 
        \end{bmatrix}.</math>     
 
   
 
<span class="exam">(a) List rank &nbsp;<math style="vertical-align: 0px">A</math>&nbsp; and &nbsp;<math style="vertical-align: 0px">\text{dim Nul }A.</math>
 
 
 
<span class="exam">(b) Find bases for &nbsp;<math style="vertical-align: 0px">\text{Col }A</math>&nbsp; and &nbsp;<math style="vertical-align: 0px">\text{Nul }A.</math>&nbsp; Find an example of a nonzero vector that belongs to &nbsp;<math style="vertical-align: -5px">\text{Col }A,</math>&nbsp; as well as an example of a nonzero vector that belongs to &nbsp;<math style="vertical-align: 0px">\text{Nul }A.</math>
 
  
  

Revision as of 19:17, 9 October 2017

If    is an    matrix such that    what are the possible values of  


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Solution:

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Final Answer:  
      

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