Skew-symmetric matrices
A real
- Show
is a subspace of . - Find an ordered basis
for the space of all skew-symmetric matrices.
View code
A real $n\times n$ matrix $A$ is called {\bfseries skew-symmetric} if $A^{\top}=-A$. Let $V_n$ be the set of all skew-symmetric matrices in $\operatorname{M}_n({\bf R})$. Recall that $\operatorname{M}_n({\bf R})$ is an $n^2$-dimensional ${\bf R}$-vector space with standard basis $\left\{e_{ij}\,|\, 1\leq i,j\leq n\right\}$, where $e_{ij}$ is the $n\times n$ matrix with a 1 in the $(i,j)$-position and zeros everywhere else.
\begin{enumerate}[label=\alph*)]
\item Show $V_n$ is a subspace of $\operatorname{M}_n({\bf R})$.
\item Find an ordered basis $\mathcal{B}$ for the space $V_3$ of all skew-symmetric $3\times 3$ matrices.
\end{enumerate}