Determine Whether the Following Argument Is Valid $\begin{array}{l}p \rightarrow r \\q \rightarrow r \\\neg(p \vee q)\end{array}$

Determine whether the following argument is valid:
$\begin{array}{l}p \rightarrow r \\q \rightarrow r \\\neg(p \vee q)\end{array}$
$\because \neg \gamma$