Proving that a linear functional is matrix trace
29583
Characterization of the trace function
22689
Reference for trace/norm inequality
97158
Prove that the operator norm is a norm
90435
Prove that there exist linear functionals $L_1, L_2$ on $X$
156877
Rank-one perturbation proof
121987
Direct proof that nilpotent matrix has zero trace
127620
Matrix exponential of a traceless $2\times2$ complex matrix
103839
Proving that $T^{2} = T$ for a linear operator on $W$ implies that $V = \operatorname{Null} T \oplus \operatorname{Range} T$
35801
Traceless matrices and commutators
75855
Show that $\det{(A + sxy^*)}$ is linear in $s$
78344
Nonconstant linear functional on a topological vector space is an open mapping
5616
How can I prove the IFF condition for this group of matrices?
137920
Proving an equation with invertible matrices
93121
How to prove there exists a linear transformation?
157269
If $\alpha_{1},\ldots,\alpha_{m}$ are vectors different from zero vector, then there is a linear functional $f$ such that $f(\alpha_{i})\neq 0$
26183
Prob. 9, Sec. 4.3 in Kreyszig's Functional Analysis Book: Proof of the Hahn Banach Theorem without Zorn's Lemma
70606
Show that the LU decomposition of matrices of the form $\left[\begin{smallmatrix}0& x\\0 & y\end{smallmatrix}\right]$ is not unique