\emph{2 pts} Arquivo resposta: N01.py.

Considere as funç\~oes:

\begin{itemize}
   \item $f_1(x)=x^4-x^3+2x^2-4x-7$;
   \item $f_2(x)=x \cos{x}+2$;
   \item $f_3(x)=e^x-\cos{x}-1$;
   \item $f_4(x)=(x-1) e^x-2$;
   \item $f_5(x)=\sin{x}-x\cos{x}-1$;
\end{itemize}

Implemente como c\'odigo Python:
\begin{enumerate}
 \item As funç\~oes, \texttt{def f\_i(x)}, $i=1,2,3,4,5$.
 \item As suas derivadas anal\'iticas, \texttt{def df\_i(x)}, $i=1,2,3,4,5$.
 \item As suas segunda derivadas anal\'iticas, \texttt{def d2f\_i(x)}, $i=1,2,3,4,5$.
\end{enumerate}

