Let $X$ be a D11: Set such that
(i) | $E_1, \ldots, E_N \subseteq X$ are each a D78: Subset |
Then
\begin{equation}
\prod_{n = 1}^N I_{E_n} = I_{\bigcap_{n = 1}^N E_n}
\end{equation}
(i) | $E_1, \ldots, E_N \subseteq X$ are each a D78: Subset |