Questions
Question 1
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Define the eigenspace \(E_\lambda\) of a matrix \(A\).
Question 2
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Why does an eigenspace include \(\mathbf0\)?
Question 3
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Find \(E_2\) for \(A=\begin{pmatrix}2&0\\0&5\end{pmatrix}\).
Question 4
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Find \(E_5\) for \(A=\begin{pmatrix}2&0\\0&5\end{pmatrix}\).
Question 5
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Find the eigenspace for \(\lambda=3\) when \(A=\begin{pmatrix}3&1\\0&3\end{pmatrix}\).
Question 6
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Find \(E_1\) for \(A=\begin{pmatrix}2&1\\1&2\end{pmatrix}\).
Question 7
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Find \(E_3\) for \(A=\begin{pmatrix}2&1\\1&2\end{pmatrix}\).
Question 8
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What is \(\dim E_4\) if \(E_4=\operatorname{span}\{(1,2,0),(0,1,1)\}\) and the two spanning vectors are independent?
Question 9
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Find \(E_2\) for \(A=\begin{pmatrix}2&0&0\\0&2&0\\0&0&5\end{pmatrix}\).
Question 10
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Find \(E_0\) for \(A=\begin{pmatrix}1&-1\\2&-2\end{pmatrix}\).
Question 11
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Explain why an eigenspace is a subspace.
Question 12
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Explain why eigenspaces for distinct eigenvalues meet only in \(\mathbf0\).
Question 13
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For which \(a\) does \(A=\begin{pmatrix}a&0\\0&3\end{pmatrix}\) have \(E_3=\mathbb R^2\)?
Question 14
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For which \(k\) does \(E_1\) of \(A=\begin{pmatrix}1&k\\0&1\end{pmatrix}\) have dimension \(2\)?
Question 15
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Find \(E_2\) for \(A=\begin{pmatrix}2&1&0\\0&2&0\\0&0&3\end{pmatrix}\).
Question 16
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Find \(E_3\) for \(A=\begin{pmatrix}2&0&0\\0&3&1\\0&0&3\end{pmatrix}\).
Question 17
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A matrix has \(E_2=\operatorname{span}\{(1,0),(0,1)\}\). What does the matrix do to every vector in \(\mathbb R^2\)?
Question 18
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A student lists \(E_4=\{(1,0),(2,0),(3,0)\}\). Explain why this is not a correct eigenspace description.
Question 19
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Prove that \(E_\lambda=\ker(A-\lambda I)\).
Question 20
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Explain why the geometric multiplicity of an eigenvalue cannot exceed its algebraic multiplicity in the examples studied.