\begin{tikzpicture}
\umlusecase[name=case1]{use case 1}
\umlusecase[x=5, name=case2]{use case 2}
\umlusecase[x=5, y=-2, name=case3]{use case 3}

\umlinclude{case1}{case2}
\umlVHextend[st:pos=1.5]{case1}{case3}
\end{tikzpicture}