\input{preamble-standalone.ltx}
\begin{document}

% Ex. No. 15 (Section  1.5 : Notations and conventions)

\begin{tikzpicture}
    \tkzDefPoints{0/0/A}
    \tkzDrawPoints(A)
    \tkzLabelPoint(A){$P$}
\end{tikzpicture}

\end{document}