Open unit ball
= Open unit ball
{title2=$B_X$}
The open unit ball of a <normed vector space> $X$ is $B_X=\{x\in X:\lVert x\rVert<1\}$.
= Open unit ball
{title2=$B_X$}
The open unit ball of a <normed vector space> $X$ is $B_X=\{x\in X:\lVert x\rVert<1\}$.