Difference between revisions of "031 Review Problems"

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'''1.''' True or false: If all the entries of a <math>7\times 7</math> matrix <math>A</math> are <math>7,</math> then det <math>A</math> must be <math>7^7.</math>
+
'''1.''' True or false: If all the entries of a &nbsp;<math>7\times 7</math>&nbsp; matrix &nbsp;<math>A</math>&nbsp; are &nbsp;<math>7,</math>&nbsp; then &nbsp;<math>\text{det }A</math>&nbsp; must be &nbsp;<math>7^7.</math>
  
 
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'''2.''' True or false: If a matrix <math>A^2</math> is diagonalizable, then the matrix <math>A</math> must be diagonalizable as well.
+
'''2.''' True or false: If a matrix &nbsp;<math>A^2</math>&nbsp; is diagonalizable, then the matrix &nbsp;<math>A</math>&nbsp; must be diagonalizable as well.
  
 
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'''3.''' True or false: If <math>A</math> is a <math>4\times 4</math> matrix with characteristic equation <math>\lambda(\lambda-1)(\lambda+1)(\lambda+e)=0,</math> then <math>A</math> is diagonalizable.
+
'''3.''' True or false: If &nbsp;<math>A</math>&nbsp; is a &nbsp;<math>4\times 4</math>&nbsp; matrix with characteristic equation &nbsp;<math>\lambda(\lambda-1)(\lambda+1)(\lambda+e)=0,</math>&nbsp; then &nbsp;<math>A</math>&nbsp; is diagonalizable.
  
 
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'''4.''' True or false: If <math>A</math> is invertible, then <math>A</math> is diagonalizable.
+
'''4.''' True or false: If &nbsp;<math>A</math>&nbsp; is invertible, then &nbsp;<math>A</math>&nbsp; is diagonalizable.
  
 
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'''5.''' True or false: If <math>A</math> and <math>B</math> are invertible <math>n\times n</math> matrices, then so is <math>A+B.</math>
+
'''5.''' True or false: If &nbsp;<math>A</math>&nbsp; and &nbsp;<math>B</math>&nbsp; are invertible &nbsp;<math>n\times n</math>&nbsp; matrices, then so is &nbsp;<math>A+B.</math>
  
 
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'''6.''' True or false: If <math>A</math> is a <math>3\times 5</math> matrix and dim Nul <math>A=2,</math> then <math>A\vec{x}=\vec{b}</math> is consistent for all <math>\vec{b}</math> in <math>\mathbb{R}^3.</math>
+
'''6.''' True or false: If &nbsp;<math>A</math>&nbsp; is a &nbsp;<math>3\times 5</math>&nbsp; matrix and &nbsp;<math>\text{dim Nul }A=2,</math>&nbsp; then &nbsp;<math>A\vec{x}=\vec{b}</math>&nbsp; is consistent for all &nbsp;<math>\vec{b}</math>&nbsp; in &nbsp;<math>\mathbb{R}^3.</math>
  
 
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'''7.''' True or false: Let <math>C=AB</math> for <math>4\times 4</math> matrices <math>A</math> and <math>B.</math> If <math>C</math> is invertible, then <math>A</math> is invertible.
+
'''7.''' True or false: Let &nbsp;<math>C=AB</math>&nbsp; for &nbsp;<math>4\times 4</math>&nbsp; matrices &nbsp;<math>A</math>&nbsp; and &nbsp;<math>B.</math>&nbsp; If &nbsp;<math>C</math>&nbsp; is invertible, then &nbsp;<math>A</math>&nbsp; is invertible.
  
 
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'''8.''' True or false: Let <math>W</math> be a subspace of <math>\mathbb{R}^4</math> and <math>\vec{v}</math> be a vector in <math>\mathbb{R}^4.</math> If <math>\vec{v}\in W</math> and <math>\vec{v}\in W^\perp,</math> then <math>\vec{v}=\vec{0}.</math>
+
'''8.''' True or false: Let &nbsp;<math>W</math>&nbsp; be a subspace of &nbsp;<math>\mathbb{R}^4</math>&nbsp; and &nbsp;<math>\vec{v}</math>&nbsp; be a vector in &nbsp;<math>\mathbb{R}^4.</math>&nbsp; If &nbsp;<math>\vec{v}\in W</math>&nbsp; and &nbsp;<math>\vec{v}\in W^\perp,</math>&nbsp; then &nbsp;<math>\vec{v}=\vec{0}.</math>
  
 
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'''9.''' True or false: If <math>A</math> is an invertible <math>3\times 3</math> matrix, and <math>B</math> and <math>C</math> are <math>3\times 3</math> matrices such that <math>AB=AC,</math> then <math>B=C.</math>
+
'''9.''' True or false: If &nbsp;<math>A</math>&nbsp; is an invertible &nbsp;<math>3\times 3</math>&nbsp; matrix, and &nbsp;<math>B</math>&nbsp; and &nbsp;<math>C</math>&nbsp; are &nbsp;<math>3\times 3</math>&nbsp; matrices such that &nbsp;<math>AB=AC,</math>&nbsp; then &nbsp;<math>B=C.</math>
  
 
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'''10.'''  
 
'''10.'''  
  
(a) Is the matrix <math>A=     
+
(a) Is the matrix &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           3 & 1 \\
 
           3 & 1 \\
 
           0 & 3  
 
           0 & 3  
         \end{bmatrix}</math> diagonalizable? If so, explain why and diagonalize it. If not, explain why not.
+
         \end{bmatrix}</math>&nbsp; diagonalizable? If so, explain why and diagonalize it. If not, explain why not.
 
          
 
          
(b) Is the matrix <math>A=     
+
(b) Is the matrix &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           2 & 0 & -2 \\
 
           2 & 0 & -2 \\
 
           1 & 3  & 2 \\
 
           1 & 3  & 2 \\
 
           0 & 0 & 3  
 
           0 & 0 & 3  
         \end{bmatrix}</math> diagonalizable? If so, explain why and diagonalize it. If not, explain why not.
+
         \end{bmatrix}</math>&nbsp; diagonalizable? If so, explain why and diagonalize it. If not, explain why not.
  
 
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'''11.''' Find the eigenvalues and eigenvectors of the matrix <math>A=     
+
'''11.''' Find the eigenvalues and eigenvectors of the matrix &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           1 & 1 & 1 \\
 
           1 & 1 & 1 \\
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|}
 
|}
  
'''12.''' Consider the matrix <math>A=     
+
'''12.''' Consider the matrix &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           1 & -4 & 9 & -7 \\
 
           1 & -4 & 9 & -7 \\
 
           -1 & 2  & -4 & 1 \\
 
           -1 & 2  & -4 & 1 \\
 
           5 & -6 & 10 & 7  
 
           5 & -6 & 10 & 7  
         \end{bmatrix}</math> and assume that it is row equivalent to the matrix  
+
         \end{bmatrix}</math>&nbsp; and assume that it is row equivalent to the matrix  
  
<math>B=     
+
::<math>B=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           1 & 0 & -1 & 5 \\
 
           1 & 0 & -1 & 5 \\
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         \end{bmatrix}.</math>       
 
         \end{bmatrix}.</math>       
 
      
 
      
(a) List rank <math>A</math> and dim Nul <math>A.</math>
+
(a) List rank &nbsp;<math>A</math>&nbsp; and &nbsp;<math>\text{dim Nul }A.</math>
  
(b) Find bases for Col <math>A</math> and Nul <math>A.</math> Find an example of a nonzero vector that belongs to Col <math>A,</math> as well as an example of a nonzero vector that belongs to Nul <math>A.</math>
+
(b) Find bases for &nbsp;<math>\text{Col }A</math>&nbsp; and &nbsp;<math>\text{Nul }A.</math>&nbsp; Find an example of a nonzero vector that belongs to &nbsp;<math>\text{Col }A,</math>&nbsp; as well as an example of a nonzero vector that belongs to &nbsp;<math>\text{Nul }A.</math>
  
 
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'''13.''' Find the dimension of the subspace spanned by the given vectors. Are these vectors linearly independent?
 
'''13.''' Find the dimension of the subspace spanned by the given vectors. Are these vectors linearly independent?
  
<math>\begin{bmatrix}
+
::<math>\begin{bmatrix}
 
           1  \\
 
           1  \\
 
           0 \\
 
           0 \\
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'''14.''' Let   
 
'''14.''' Let   
<math>B=     
+
&nbsp;<math>B=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           1 & -2 & 3 & 4\\
 
           1 & -2 & 3 & 4\\
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  </math>
 
  </math>
 
    
 
    
(a) Is <math>B</math> invertible? Explain.
+
(a) Is &nbsp;<math>B</math>&nbsp; invertible? Explain.
  
(b) Define a linear transformation <math>T</math> by the formula <math>T(\vec{x})=B\vec{x}.</math> Is <math>T</math> onto? Explain.
+
(b) Define a linear transformation &nbsp;<math>T</math>&nbsp; by the formula &nbsp;<math>T(\vec{x})=B\vec{x}.</math>&nbsp; Is &nbsp;<math>T</math>&nbsp; onto? Explain.
  
 
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'''15.''' Suppose <math>T</math> is a linear transformation given by the formula  
+
'''15.''' Suppose &nbsp;<math>T</math>&nbsp; is a linear transformation given by the formula  
  
<math>T\Bigg(
+
::<math>T\Bigg(
 
\begin{bmatrix}
 
\begin{bmatrix}
 
           x_1 \\
 
           x_1 \\
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         \end{bmatrix}</math>
 
         \end{bmatrix}</math>
 
          
 
          
(a) Find the standard matrix for <math>T.</math>
+
(a) Find the standard matrix for &nbsp;<math>T.</math>
 
          
 
          
(b) Let <math>\vec{u}=7\vec{e_1}-4\vec{e_2}.</math> Find <math>T(\vec{u}).</math>
+
(b) Let &nbsp;<math>\vec{u}=7\vec{e_1}-4\vec{e_2}.</math>&nbsp; Find &nbsp;<math>T(\vec{u}).</math>
 
          
 
          
(c) Is <math>\begin{bmatrix}
+
(c) Is &nbsp;<math>\begin{bmatrix}
 
           -1 \\
 
           -1 \\
 
           3  
 
           3  
         \end{bmatrix}</math> in the range of <math>T?</math> Explain.
+
         \end{bmatrix}</math>&nbsp; in the range of &nbsp;<math>T?</math>&nbsp; Explain.
  
 
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'''16.''' Let <math>A</math> and <math>B</math> be <math>6\times 6</math> matrices with det <math>A=-10</math> and det <math>B=5.</math> Use properties of  
+
'''16.''' Let &nbsp;<math>A</math>&nbsp; and &nbsp;<math>B</math>&nbsp; be &nbsp;<math>6\times 6</math>&nbsp; matrices with &nbsp;<math>\text{det }A=-10</math>&nbsp; and &nbsp;<math>\text{det }B=5.</math>&nbsp; Use properties of determinants to compute:
  
determinants to compute:
+
(a) &nbsp;<math>\text{det }3A</math>
  
(a) det <math>3A</math>
+
(b) &nbsp;<math>\text{det }(A^TB^{-1})</math>
 
 
(b) det <math>(A^TB^{-1})</math>
 
  
 
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'''17.''' Let <math>A=     
+
'''17.''' Let &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           5 & 1 \\
 
           5 & 1 \\
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         \end{bmatrix}.</math>
 
         \end{bmatrix}.</math>
  
(a) Find a basis for the eigenspace(s) of <math>A.</math>
+
(a) Find a basis for the eigenspace(s) of &nbsp;<math>A.</math>
  
(b) Is the matrix <math>A</math> diagonalizable? Explain.
+
(b) Is the matrix &nbsp;<math>A</math>&nbsp; diagonalizable? Explain.
  
 
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'''18.''' Let <math>\vec{v}=\begin{bmatrix}
+
'''18.''' Let &nbsp;<math>\vec{v}=\begin{bmatrix}
 
           -1 \\
 
           -1 \\
 
           3 \\
 
           3 \\
 
           0
 
           0
         \end{bmatrix}</math> and <math>\vec{y}=\begin{bmatrix}
+
         \end{bmatrix}</math>&nbsp; and &nbsp;<math>\vec{y}=\begin{bmatrix}
 
           2 \\
 
           2 \\
 
           0 \\
 
           0 \\
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         \end{bmatrix}.</math>
 
         \end{bmatrix}.</math>
 
          
 
          
(a) Find a unit vector in the direction of <math>\vec{v}.</math>
+
(a) Find a unit vector in the direction of &nbsp;<math>\vec{v}.</math>
 
          
 
          
(b) Find the distance between <math>\vec{v}</math> and <math>\vec{y}.</math>
+
(b) Find the distance between &nbsp;<math>\vec{v}</math>&nbsp; and &nbsp;<math>\vec{y}.</math>
 
          
 
          
(c) Let <math>L=</math>Span<math>\{\vec{v}\}.</math> Compute the orthogonal projection of <math>\vec{y}</math> onto <math>L.</math>
+
(c) Let &nbsp;<math>L=\text{Span }\{\vec{v}\}.</math>&nbsp; Compute the orthogonal projection of &nbsp;<math>\vec{y}</math>&nbsp; onto &nbsp;<math>L.</math>
  
 
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'''19.''' Let <math>W=</math>Span<math>\Bigg\{\begin{bmatrix}
+
'''19.''' Let &nbsp;<math>W=\text{Span }\Bigg\{\begin{bmatrix}
 
           2 \\
 
           2 \\
 
           0 \\
 
           0 \\
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           0 \\
 
           0 \\
 
           0
 
           0
         \end{bmatrix}\Bigg\}.</math> Is <math>\begin{bmatrix}
+
         \end{bmatrix}\Bigg\}.</math>&nbsp; Is &nbsp;<math>\begin{bmatrix}
 
           2 \\
 
           2 \\
 
           6 \\
 
           6 \\
 
           4 \\
 
           4 \\
 
           0
 
           0
         \end{bmatrix}</math> in <math>W^\perp?</math> Explain.
+
         \end{bmatrix}</math>&nbsp; in &nbsp;<math>W^\perp?</math>&nbsp; Explain.
  
 
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'''20.'''  
 
'''20.'''  
  
(a) Let <math>T:\mathbb{R}^2\rightarrow \mathbb{R}^2</math> be a transformation given by  
+
(a) Let &nbsp;<math>T:\mathbb{R}^2\rightarrow \mathbb{R}^2</math>&nbsp; be a transformation given by  
  
<math>T\bigg(
+
::<math>T\bigg(
 
\begin{bmatrix}
 
\begin{bmatrix}
 
           x \\
 
           x \\
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         \end{bmatrix}.</math>
 
         \end{bmatrix}.</math>
  
Determine whether <math>T</math> is a linear transformation. Explain.
+
Determine whether &nbsp;<math>T</math>&nbsp; is a linear transformation. Explain.
  
(b) Let <math>A=     
+
(b) Let &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           1 & -3 & 0 \\
 
           1 & -3 & 0 \\
 
           -4 & 1 &1
 
           -4 & 1 &1
         \end{bmatrix}</math> and <math>B=     
+
         \end{bmatrix}</math>&nbsp; and &nbsp;<math>B=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           2 & 1\\
 
           2 & 1\\
 
           1 & 0 \\
 
           1 & 0 \\
 
           -1 & 1
 
           -1 & 1
         \end{bmatrix}.</math> Find <math>AB,</math> <math>BA^T</math> and <math>A-B^T.</math>
+
         \end{bmatrix}.</math>&nbsp; Find &nbsp;<math>AB,</math>&nbsp; &nbsp;<math>BA^T</math>&nbsp; and &nbsp;<math>A-B^T.</math>
  
 
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'''21.''' Let <math>A=     
+
'''21.''' Let &nbsp;<math>A=     
 
     \begin{bmatrix}
 
     \begin{bmatrix}
 
           1 & 3 & 8 \\
 
           1 & 3 & 8 \\
 
           2 & 4 &11\\
 
           2 & 4 &11\\
 
           1 & 2 & 5
 
           1 & 2 & 5
         \end{bmatrix}.</math> Find <math>A^{-1}</math> if possible.
+
         \end{bmatrix}.</math>&nbsp; Find &nbsp;<math>A^{-1}</math>&nbsp; if possible.
  
 
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'''22.''' Find a formula for <math>\begin{bmatrix}
+
'''22.''' Find a formula for &nbsp;<math>\begin{bmatrix}
 
           1 & -6  \\
 
           1 & -6  \\
 
           2 & -6  
 
           2 & -6  
         \end{bmatrix}^k</math> by diagonalizing the matrix.
+
         \end{bmatrix}^k</math>&nbsp; by diagonalizing the matrix.
  
 
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'''23.'''  
 
'''23.'''  
  
(a) Show that if <math>\vec{x}</math> is an eigenvector of the matrix <math>A</math> corresponding to the eigenvalue 2, then <math>\vec{x}</math> is an eigenvector of <math>A^3-A^2+I.</math> What is the corresponding eigenvalue?
+
(a) Show that if &nbsp;<math>\vec{x}</math>&nbsp; is an eigenvector of the matrix &nbsp;<math>A</math>&nbsp; corresponding to the eigenvalue 2, then &nbsp;<math>\vec{x}</math>&nbsp; is an eigenvector of &nbsp;<math>A^3-A^2+I.</math>&nbsp; What is the corresponding eigenvalue?
  
(b) Show that if <math>\vec{y}</math> is an eigenvector of the matrix <math>A</math> corresponding to the eigenvalue 3 and <math>A</math> is invertible, then <math>\vec{y}</math> is an eigenvector of <math>A^{-1}.</math> What is the corresponding eigenvalue?
+
(b) Show that if &nbsp;<math>\vec{y}</math>&nbsp; is an eigenvector of the matrix &nbsp;<math>A</math>&nbsp; corresponding to the eigenvalue 3 and &nbsp;<math>A</math>&nbsp; is invertible, then &nbsp;<math>\vec{y}</math>&nbsp; is an eigenvector of &nbsp;<math>A^{-1}.</math>&nbsp; What is the corresponding eigenvalue?
  
 
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'''24.''' Let <math>A=\begin{bmatrix}
+
'''24.''' Let &nbsp;<math>A=\begin{bmatrix}
 
           3 & 0 & -1 \\
 
           3 & 0 & -1 \\
 
           0 & 1 &-3\\
 
           0 & 1 &-3\\
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         \end{bmatrix}.</math>  
 
         \end{bmatrix}.</math>  
  
Use the Diagonalization Theorem to find the eigenvalues of <math>A</math> and a basis for each eigenspace.
+
Use the Diagonalization Theorem to find the eigenvalues of &nbsp;<math>A</math>&nbsp; and a basis for each eigenspace.
  
 
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'''25.''' Give an example of a <math>3\times 3</math> matrix <math>A</math> with eigenvalues 5,-1 and 3.
+
'''25.''' Give an example of a &nbsp;<math>3\times 3</math>&nbsp; matrix &nbsp;<math>A</math>&nbsp; with eigenvalues 5,-1 and 3.
  
 
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'''26.''' Assume <math>A^2=I.</math> Find Nul <math>A.</math>
+
'''26.''' Assume &nbsp;<math>A^2=I.</math>&nbsp; Find &nbsp;<math>\text{Nul }A.</math>
  
 
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'''27.''' If <math>A</math> is an <math>n\times n</math> matrix such that <math>AA^T=I,</math> what are the possible values of det <math>A?</math>
+
'''27.''' If &nbsp;<math>A</math>&nbsp; is an &nbsp;<math>n\times n</math>&nbsp; matrix such that &nbsp;<math>AA^T=I,</math>&nbsp; what are the possible values of &nbsp;<math>\text{det }A?</math>
  
 
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'''28.''' Show that if <math>\vec{x}</math> is an eigenvector of the matrix product <math>AB</math> and <math>B\vec{x}\ne \vec{0},</math> then <math>B\vec{x}</math> is an eigenvector of <math>BA.</math>
+
'''28.''' Show that if &nbsp;<math>\vec{x}</math>&nbsp; is an eigenvector of the matrix product &nbsp;<math>AB</math>&nbsp; and &nbsp;<math>B\vec{x}\ne \vec{0},</math>&nbsp; then &nbsp;<math>B\vec{x}</math>&nbsp; is an eigenvector of &nbsp;<math>BA.</math>
  
 
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'''29.'''  
 
'''29.'''  
  
(a) Suppose a <math>6\times 8</math> matrix <math>A</math> has 4 pivot columns. What is dim Nul <math>A?</math> Is Col <math>A=\mathbb{R}^4?</math> Why or why not?
+
(a) Suppose a &nbsp;<math>6\times 8</math>&nbsp; matrix &nbsp;<math>A</math>&nbsp; has 4 pivot columns. What is &nbsp;<math>\text{dim Nul }A?</math>&nbsp; Is &nbsp;<math>\text{Col }A=\mathbb{R}^4?</math>&nbsp; Why or why not?
  
(b) If <math>A</math> is a <math>7\times 5</math> matrix, what is the smallest possible dimension of Nul <math>A?</math>
+
(b) If &nbsp;<math>A</math>&nbsp; is a &nbsp;<math>7\times 5</math>&nbsp; matrix, what is the smallest possible dimension of &nbsp;<math>\text{Nul }A?</math>
  
 
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'''30.''' Consider the following system of equations.
 
'''30.''' Consider the following system of equations.
  
<math>x_1+kx_2=1</math>
+
::<math>x_1+kx_2=1</math>
  
<math>3x_1+5x_2=2k</math>
+
::<math>3x_1+5x_2=2k</math>
  
Find all real values of <math>k</math> such that the system has only one solution.
+
Find all real values of &nbsp;<math>k</math>&nbsp; such that the system has only one solution.
  
 
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'''31.''' Suppose <math>\{\vec{u},\vec{v}\}</math> is a basis of the eigenspace corresponding to the eigenvalue 0 of a <math>5\times 5</math> matrix <math>A.</math>
+
'''31.''' Suppose &nbsp;<math>\{\vec{u},\vec{v}\}</math>&nbsp; is a basis of the eigenspace corresponding to the eigenvalue 0 of a &nbsp;<math>5\times 5</math>&nbsp; matrix &nbsp;<math>A.</math>
  
(a) Is <math>\vec{w}=\vec{u}-2\vec{v}</math> an eigenvector of <math>A?</math> If so, find the corresponding eigenvalue.  
+
(a) Is &nbsp;<math>\vec{w}=\vec{u}-2\vec{v}</math>&nbsp; an eigenvector of &nbsp;<math>A?</math>&nbsp; If so, find the corresponding eigenvalue.  
  
 
If not, explain why.
 
If not, explain why.
  
(b) Find the dimension of Col <math>A.</math>
+
(b) Find the dimension of &nbsp;<math>\text{Col }A.</math>
  
 
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{| class="mw-collapsible mw-collapsed" style = "text-align:left;"

Revision as of 10:33, 25 August 2017

This is a list of sample problems and is meant to represent the material usually covered in Math 31. An actual test may or may not be similar.


1. True or false: If all the entries of a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 7\times 7}   matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   are  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 7,}   then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{det }A}   must be  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 7^7.}

Solution:  
Final Answer:  

2. True or false: If a matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A^2}   is diagonalizable, then the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   must be diagonalizable as well.

Solution:  
Final Answer:  

3. True or false: If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 4\times 4}   matrix with characteristic equation  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \lambda(\lambda-1)(\lambda+1)(\lambda+e)=0,}   then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is diagonalizable.

Solution:  
Final Answer:  

4. True or false: If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is invertible, then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is diagonalizable.

Solution:  
Final Answer:  

5. True or false: If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B}   are invertible  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle n\times n}   matrices, then so is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A+B.}

Solution:  
Final Answer:  

6. True or false: If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 3\times 5}   matrix and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{dim Nul }A=2,}   then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A\vec{x}=\vec{b}}   is consistent for all  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{b}}   in  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbb{R}^3.}

Solution:  
Final Answer:  

7. True or false: Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle C=AB}   for  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 4\times 4}   matrices  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B.}   If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle C}   is invertible, then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is invertible.

Solution:  
Final Answer:  

8. True or false: Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle W}   be a subspace of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathbb{R}^4}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{v}}   be a vector in    If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{v}\in W}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{v}\in W^\perp,}   then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{v}=\vec{0}.}

Solution:  
Final Answer:  

9. True or false: If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is an invertible  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 3\times 3}   matrix, and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle C}   are  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 3\times 3}   matrices such that  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle AB=AC,}   then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B=C.}

Solution:  
Final Answer:  

10.

(a) Is the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 3 & 1 \\ 0 & 3 \end{bmatrix}}   diagonalizable? If so, explain why and diagonalize it. If not, explain why not.

(b) Is the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 2 & 0 & -2 \\ 1 & 3 & 2 \\ 0 & 0 & 3 \end{bmatrix}}   diagonalizable? If so, explain why and diagonalize it. If not, explain why not.

Solution:  
Final Answer:  

11. Find the eigenvalues and eigenvectors of the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 1 & 1 & 1 \\ 0 & -1 & 1 \\ 0 & 0 & 2 \end{bmatrix}.}

Solution:  
Final Answer:  

12. Consider the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 1 & -4 & 9 & -7 \\ -1 & 2 & -4 & 1 \\ 5 & -6 & 10 & 7 \end{bmatrix}}   and assume that it is row equivalent to the matrix

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B= \begin{bmatrix} 1 & 0 & -1 & 5 \\ 0 & -2 & 5 & -6 \\ 0 & 0 & 0 & 0 \end{bmatrix}.}

(a) List rank  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{dim Nul }A.}

(b) Find bases for  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Col }A}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Nul }A.}   Find an example of a nonzero vector that belongs to  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Col }A,}   as well as an example of a nonzero vector that belongs to  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Nul }A.}

Solution:  
Final Answer:  

13. Find the dimension of the subspace spanned by the given vectors. Are these vectors linearly independent?

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{bmatrix} 1 \\ 0 \\ 2 \end{bmatrix}, \begin{bmatrix} 3 \\ 1 \\ 1 \end{bmatrix}, \begin{bmatrix} -2 \\ -1 \\ 1 \end{bmatrix}, \begin{bmatrix} 5 \\ 2 \\ 2 \end{bmatrix}}
Solution:  
Final Answer:  

14. Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B= \begin{bmatrix} 1 & -2 & 3 & 4\\ 0 & 3 &0 &0\\ 0 & 5 & 1 & 2\\ 0 & -1 & 3 & 6 \end{bmatrix}. }

(a) Is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B}   invertible? Explain.

(b) Define a linear transformation  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T}   by the formula  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T(\vec{x})=B\vec{x}.}   Is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T}   onto? Explain.

Solution:  
Final Answer:  

15. Suppose  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T}   is a linear transformation given by the formula

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T\Bigg( \begin{bmatrix} x_1 \\ x_2 \\ x_3 \\ \end{bmatrix} \Bigg)= \begin{bmatrix} 5x_1-2.5x_2+10x_3 \\ -x_1+0.5x_2-2x_3 \end{bmatrix}}

(a) Find the standard matrix for  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T.}

(b) Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{u}=7\vec{e_1}-4\vec{e_2}.}   Find  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T(\vec{u}).}

(c) Is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{bmatrix} -1 \\ 3 \end{bmatrix}}   in the range of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T?}   Explain.

Solution:  
Final Answer:  

16. Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B}   be  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6\times 6}   matrices with  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{det }A=-10}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{det }B=5.}   Use properties of determinants to compute:

(a)  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{det }3A}

(b)  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{det }(A^TB^{-1})}

Solution:  
Final Answer:  

17. Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 5 & 1 \\ 0 & 5 \end{bmatrix}.}

(a) Find a basis for the eigenspace(s) of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A.}

(b) Is the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   diagonalizable? Explain.

Solution:  
Final Answer:  

18. Let    and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{y}=\begin{bmatrix} 2 \\ 0 \\ 5 \end{bmatrix}.}

(a) Find a unit vector in the direction of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{v}.}

(b) Find the distance between  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{v}}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{y}.}

(c) Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle L=\text{Span }\{\vec{v}\}.}   Compute the orthogonal projection of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{y}}   onto  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle L.}

Solution:  
Final Answer:  

19. Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle W=\text{Span }\Bigg\{\begin{bmatrix} 2 \\ 0 \\ -1 \\ 0 \end{bmatrix},\begin{bmatrix} -3 \\ 1 \\ 0 \\ 0 \end{bmatrix}\Bigg\}.}   Is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{bmatrix} 2 \\ 6 \\ 4 \\ 0 \end{bmatrix}}   in  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle W^\perp?}   Explain.

Solution:  
Final Answer:  

20.

(a) Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T:\mathbb{R}^2\rightarrow \mathbb{R}^2}   be a transformation given by

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T\bigg( \begin{bmatrix} x \\ y \end{bmatrix} \bigg)= \begin{bmatrix} 1-xy \\ x+y \end{bmatrix}.}

Determine whether  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T}   is a linear transformation. Explain.

(b) Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 1 & -3 & 0 \\ -4 & 1 &1 \end{bmatrix}}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B= \begin{bmatrix} 2 & 1\\ 1 & 0 \\ -1 & 1 \end{bmatrix}.}   Find  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle AB,}    Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle BA^T}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A-B^T.}

Solution:  
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21. Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A= \begin{bmatrix} 1 & 3 & 8 \\ 2 & 4 &11\\ 1 & 2 & 5 \end{bmatrix}.}   Find  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A^{-1}}   if possible.

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22. Find a formula for  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{bmatrix} 1 & -6 \\ 2 & -6 \end{bmatrix}^k}   by diagonalizing the matrix.

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23.

(a) Show that if  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{x}}   is an eigenvector of the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   corresponding to the eigenvalue 2, then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{x}}   is an eigenvector of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A^3-A^2+I.}   What is the corresponding eigenvalue?

(b) Show that if  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{y}}   is an eigenvector of the matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   corresponding to the eigenvalue 3 and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is invertible, then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{y}}   is an eigenvector of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A^{-1}.}   What is the corresponding eigenvalue?

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24. Let  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A=\begin{bmatrix} 3 & 0 & -1 \\ 0 & 1 &-3\\ 1 & 0 & 0 \end{bmatrix}\begin{bmatrix} 3 & 0 & 0 \\ 0 & 4 &0\\ 0 & 0 & 3 \end{bmatrix}\begin{bmatrix} 0 & 0 & 1 \\ -3 & 1 &9\\ -1 & 0 & 3 \end{bmatrix}.}

Use the Diagonalization Theorem to find the eigenvalues of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   and a basis for each eigenspace.

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25. Give an example of a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 3\times 3}   matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   with eigenvalues 5,-1 and 3.

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26. Assume  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A^2=I.}   Find  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Nul }A.}

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27. If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is an  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle n\times n}   matrix such that  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle AA^T=I,}   what are the possible values of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{det }A?}

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28. Show that if  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{x}}   is an eigenvector of the matrix product  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle AB}   and  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B\vec{x}\ne \vec{0},}   then  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle B\vec{x}}   is an eigenvector of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle BA.}

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29.

(a) Suppose a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6\times 8}   matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   has 4 pivot columns. What is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{dim Nul }A?}   Is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Col }A=\mathbb{R}^4?}   Why or why not?

(b) If  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A}   is a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 7\times 5}   matrix, what is the smallest possible dimension of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Nul }A?}

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30. Consider the following system of equations.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x_1+kx_2=1}
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 3x_1+5x_2=2k}

Find all real values of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle k}   such that the system has only one solution.

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31. Suppose  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \{\vec{u},\vec{v}\}}   is a basis of the eigenspace corresponding to the eigenvalue 0 of a  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 5\times 5}   matrix  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A.}

(a) Is  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \vec{w}=\vec{u}-2\vec{v}}   an eigenvector of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A?}   If so, find the corresponding eigenvalue.

If not, explain why.

(b) Find the dimension of  Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \text{Col }A.}

Solution:  
Final Answer: