Definition 10.1.9 (Balanced/Circled).label Let $E$ be a vector space over $K \in \RC$ and $A \subset E$, then $A$ is balanced/circled if $\lambda A \subset A$ for all $\lambda \in K$ with $\abs{\lambda}\le 1$.
Definition 10.1.9 (Balanced/Circled).label Let $E$ be a vector space over $K \in \RC$ and $A \subset E$, then $A$ is balanced/circled if $\lambda A \subset A$ for all $\lambda \in K$ with $\abs{\lambda}\le 1$.