Kerodon

$\Newextarrow{\xRightarrow}{5,5}{0x21D2}$
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$

Example 3.3.4.6. Let $X$ be a discrete simplicial set (Definition 1.1.4.9). Then the maps

\[ \rho _{X}: X \rightarrow \operatorname{Ex}(X) \quad \quad \lambda _{X}: \operatorname{Sd}(X) \rightarrow X \]

are isomorphisms.