Let $x_1, w_1, \ldots, z_N, w_N \in \mathbb{C}$ each be a D1207: Complex number such that
| (i) | \begin{equation} \forall \, n \in \{ 1, \ldots, N \} : |z_n|, |w_n| \leq 1 \end{equation} |
Then
\begin{equation}
\left| \prod_{n = 1}^N z_n - \prod_{n = 1}^N w_n \right|
\leq \sum_{n = 1}^N |z_n - w_n|
\end{equation}