When is every matrix in the span of two matrices singular?
63260
Matrices whose Linear Combinations are All Singular
120937
Matrices that commute with all matrices
40222
Matrices that are not diagonal or triangular, whose eigenvalues are the diagonal elements
39334
Non-degenerate bilinear forms and invertible matrices
22222
Properties of zero-diagonal symmetric matrices
145980
For every matrix $A\in M_{2}( \mathbb{C}) $ there's  $X\in M_{2}( \mathbb{C})$ such that $X^2=A$?
127719
Is the matrix $R$ in the $QR$ decomposition unique?
2109
Max dimension of a subspace of singular $n\times n$ matrices
121062
Given a matrix, is there always another matrix which commutes with it?
32064
Zero-dimensional matrices
126337
Eigenvalues in orthogonal matrices
117175
Proof that the 2-norm of orthogonal transformation of a matrix is invariant
6267
Matrices: system that is "computationally singular" versus "exactly singular"
52208
Show that a matrix $A$ is singular if and only if $0$ is an eigenvalue.
65628
what happens to rank of matrices when singular matrix multiply by non-singular matrix??
12927
$A^2+B^2=AB$ and $BA-AB$ is non-singular
13948
Matrix in a matrix