Kaidah Pencacahan

Solusi 1:

\(4! = 4 \:.\:  3 \:.\:  2 \:.\:  1 = 24\)

Solusi 2:

\begin{equation*}
\begin{split}
_{4}P_4 & = \frac{4!}{(4 - 4)!} \\
_{4}P_4 & = \frac{4!}{0!} \\
_{4}P_4 & = \frac{4 \:.\: 3 \:.\: 2 \:.\: 1}{1} \\
_{4}P_4 & = 24
\end{split}
\end{equation*}