Is there a real matrix such that $B^2=A$
31149
Prove that matrix can be square of matrix with real entries
25357
Matrices $B$ that commute with every matrix commuting with $A$
35080
If matrices $A$ and $B$ commute, $A$ with distinct eigenvalues, then $B$ is a polynomial in $A$
58595
Existence of a G-invariant matrix
52882
find nonsingular matrices $B$ and $C$ that satisfy $BC+ CB= 0$
81176
A normal matrix with real eigenvalues is Hermitian
24809
For all square matrices $A$ and $B$ of the same size, it is true that $(A+B)^2 = A^2 + 2AB + B^2$?
146243
Does there exist a matrix $\mathbf{A}\in\mathbb{R}^{3\times3}$ such that $\mathbf{A}^{2}=-\mathbf{I}$?
130799
Matrix of rank 1; show that $A^2=cA$ for some scalar $c$.
147207
Is it always true that $\det(A^2+B^2)\geq0$?
155275
If two real matrices are conjugated over $\mathbb{C}$, are they then also conjugated over $\mathbb{R}$?
97654
Rewrite a real polynomial in real (but only linear and quadratic) factors
150714
Quick question: matrix with norm equal to spectral radius
115296
Under what conditions does a matrix $A$ have a square root?
121062
Given a matrix, is there always another matrix which commutes with it?
6960
Necessary and sufficient condition for the matrix $A = I - 2 x x^t$ to be orthogonal
55062
$2\times 2$ matrix $C=AB-BA$