\begin{definition}[Definition:Homogeneous Function/Real Space/Degree]
Let $f: \R^2 \to \R$ be a homogeneous function of two variables:
:$\exists n \in \Z: \forall t \in \R: \map f {t x, t y} = t^n \map f {x, y}$
The integer $n$ is known as the '''degree''' of $f$.
\end{definition}