Add missing \lstinline for 'homotopy'

chapters/operatorsandexpressions.tex

@@ -708,7 +708,7 @@ \subsection{Derivative and Special Purpose Operators with Function Syntax}\label
   \begin{example}
   $\mathit{actual} \cdot \lambda + \mathit{simplified} \cdot (1 - \lambda)$, where $\lambda$ is a homotopy parameter going from 0 to 1.
   \end{example}
-  The solution must fulfill the equations for homotopy returning $\mathit{actual}$.
+  The solution must fulfill the equations for \lstinline!homotopy! returning $\mathit{actual}$.
 \end{enumerate}
 For non-scalar arguments the function is vectorized according to \cref{scalar-functions-applied-to-array-arguments}.  For further details, see \cref{homotopy}.
 \end{semantics}