Let \((X, d)\) be a metric space and \(A\subseteq X\) a nonempty subset. The diameter of \(A\) is \[ \diam(A) \coloneqq \sup_{p, q\in A}d(p, q) \in [0, \infty] .\]
Diameter of a subset of a metric space
D-B7CYY
D-B7CYY
Let \((X, d)\) be a metric space and \(A\subseteq X\) a nonempty subset. The diameter of \(A\) is \[ \diam(A) \coloneqq \sup_{p, q\in A}d(p, q) \in [0, \infty] .\]