$\lambda$ is an eigenvalue of $A$ if and only if $\lambda$ is an eigenvalue of $A^T$
50384
A matrix and its transpose have the same set of eigenvalues/other version: $A$ and $A^T$ have the same spectrum
98541
If a Matrix Has Only Zero as an Eigen-Value Then It Is Nilpotent
10001
Prove that the only eigenvalue of a nilpotent operator is 0?
97733
Can it be determined that the sum of the diagonal entries, of matrix A, equals the sum of eigenvalues of A
7457
Prove that $J^+AJ$ has positive eigenvalues
72046
Prove all eigenvalues of $A^*A$ are non-negative
104424
If each eigenvalueof $A$ is either $+1$ or $-1$ $ \Rightarrow$ $A$ is similar to ${A^{ - 1}}$
22149
How to prove $dim(Ker (A- \lambda I))=dim (Ker(A^t- \lambda I))$?
35080
If matrices $A$ and $B$ commute, $A$ with distinct eigenvalues, then $B$ is a polynomial in $A$
94424
Matrices and Eigenvalues of Norm
64747
If $A^m=I$ then A is Diagonalizable
30049
If $T^m$ is diagonalizable for a $m\in\mathbb N$, then $T$ is diagonalizable.
80346
If every eigenvector of $T$ is also an eigenvector of $T^{*}$ then $T$ is a normal operator
61274
If $AA^T$ is the zero matrix, then $A$ is the zero matrix
136643
Continuity of eigenvalues and spectral radius for a general matrix
129977
Prove that $\lambda_1^2$, $\lambda_1\lambda_2$ and $\lambda_2^2$ are eigenvalues of matrix $A$
116539
Eigenvalues of matrix satisfying $A^2 = A$