Set of symmetric matrices is closed
41611
Open and closed set in n by n matrices space.
40154
Finding the dimension of real symmetric matrices with trace zero
156101
Is the convex hull of closed set in $\mathbb R^{n}$ is closed?
26592
The symmetric Difference
99678
Is a sphere a closed set?
19649
A question about the proof of "a symmetric matrix has real eigenvalues".
17217
Linear algebra skew symmetric
63260
Matrices whose Linear Combinations are All Singular
73286
Show that the set of all symmetric, real matrices is a subspace, determine the dimension
19132
Similar matrices have the same eigenvalues with the same geometric multiplicity
13906
How to prove the set $S$ is closed under the binary operation $a*b=a+b+kab$?
33955
Geometric series of matrices
140225
Linear transformation maps the first quadrant to a closed set
58149
Working with symmetric polynomials
92774
Prove that a linear subspace of $C([0,1])$ is closed
131611
$A^TA$ is always a symmetric matrix?
128835
Compactness of the set of $n \times n$ orthogonal matrices