let $x$ be a eigenvector for $Q$
126337
Eigenvalues in orthogonal matrices
123803
If $X^n$ is a diagonal matrix with distinct eigenvalues, then is $X$ also a diagonal matrix with distinct eigenvalues?
72046
Prove all eigenvalues of $A^*A$ are non-negative
76477
Eigenvalues with transpose question.
37836
Generalized eigenvectors in MATLAB?
59973
Eigenvalues and power of a matrix
81275
Eigenvalue Problem -- prove eigenvalue for $A^2 + I$
3544
Eigenvectors of a circulant matrix
94424
Matrices and Eigenvalues of Norm
98541
If a Matrix Has Only Zero as an Eigen-Value Then It Is Nilpotent
136643
Continuity of eigenvalues and spectral radius for a general matrix
10001
Prove that the only eigenvalue of a nilpotent operator is 0?
129977
Prove that $\lambda_1^2$, $\lambda_1\lambda_2$ and $\lambda_2^2$ are eigenvalues of matrix $A$
128453
If $A$ has two eigenvalues $\lambda _1, \lambda_2$ and $\dim (E_{\lambda_1})=n-1$, then $A$ is diagonalizable
35013
Demonstration: If all vectors of $V$ are eigenvectors of $T$, then there is one $\lambda$ such that $T(v) = \lambda v$ for all $v \in V$.
127719
Is the matrix $R$ in the $QR$ decomposition unique?
56818
Prove that if $A$ is positive, then $\exists\;\alpha>0$ such that $\langle Ax, x \rangle\geq \alpha|x|^2$ for $x\in\Bbb{R}^n$