Kerodon

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

Exercise 1.4.6.6. Let $f: A_{\bullet } \hookrightarrow B_{\bullet }$ be an inner anodyne morphism of simplicial sets. Show that the underlying map on vertices $A_0 \rightarrow B_0$ is a bijection.