Questions
Question 1
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What condition must a non-zero vector \(\mathbf v\) satisfy to be an eigenvector of \(A\)?
Question 2
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Why is \(\mathbf0\) not called an eigenvector?
Question 3
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Check whether \((1,0)\) is an eigenvector of \(A=\begin{pmatrix}5&2\\0&3\end{pmatrix}\).
Question 4
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If \(\mathbf v\) is an eigenvector with eigenvalue \(4\), what is \(A(3\mathbf v)\)?
Question 5
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Find an eigenvector for \(A=\begin{pmatrix}2&0\\0&5\end{pmatrix}\) with eigenvalue \(2\).
Question 6
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Find an eigenvector for \(A=\begin{pmatrix}1&0\\0&-3\end{pmatrix}\) with eigenvalue \(-3\).
Question 7
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Check whether \((1,1)\) is an eigenvector of \(A=\begin{pmatrix}2&1\\1&2\end{pmatrix}\).
Question 8
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Check whether \((1,2)\) is an eigenvector of \(A=\begin{pmatrix}1&0\\0&3\end{pmatrix}\).
Question 9
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Find eigenvectors for \(A=\begin{pmatrix}2&1\\1&2\end{pmatrix}\) with eigenvalue \(1\).
Question 10
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Find eigenvectors for \(A=\begin{pmatrix}4&1\\0&4\end{pmatrix}\) with eigenvalue \(4\).
Question 11
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Explain why any non-zero scalar multiple of an eigenvector is also an eigenvector.
Question 12
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Interpret an eigenvector of a stretching matrix physically.
Question 13
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For which \(k\) is \((1,1)\) an eigenvector of \(A=\begin{pmatrix}2&k\\1&3\end{pmatrix}\)?
Question 14
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For which \(a\) is \((1,-1)\) an eigenvector of \(A=\begin{pmatrix}a&2\\3&1\end{pmatrix}\)?
Question 15
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Find eigenvectors for \(A=\begin{pmatrix}3&2\\0&1\end{pmatrix}\) for each eigenvalue.
Question 16
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Find all \(t\) such that \((1,t)\) is an eigenvector of \(A=\begin{pmatrix}0&1\\2&1\end{pmatrix}\).
Question 17
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A matrix has eigenvectors \((1,0)\) and \((1,1)\) with eigenvalues \(2\) and \(5\). Find \(A(3,2)\).
Question 18
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A student finds \((0,0)\) while solving \((A-\lambda I)\mathbf v=\mathbf0\) and lists it as an eigenvector. Explain the error.
Question 19
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Prove that eigenvectors belonging to distinct eigenvalues of a \(2\times2\) matrix are linearly independent.
Question 20
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Explain why solving \(A\mathbf v=\mathbf0\) usually does not find eigenvectors for a non-zero eigenvalue.