
\documentclass[portuges,a4paper]{article}
\usepackage{babel}
\usepackage[mathletters]{ucs}
\usepackage[utf8x]{inputenc}

\usepackage[T1]{fontenc}
\usepackage{tikz}
\begin{document}

\title{}
\author{José João Dias de Almeida}
\date{\today}
\maketitle
\begin{abstract}

\end{abstract}

%\tableofcontents

\section{Exemplo 1           }

\begin{tikzpicture}
\draw (-1.5,0) -- (1.5,0);
\draw (0,-1.5) -- (0,1.5);
\draw (-1,0) .. controls (-1,0.555) and (-0.555,1) .. (0,1)
.. controls (0.555,1) and (1,0.555) .. (1,0);
\end{tikzpicture}

\begin{tikzpicture}
\path node at ( 0,2) [shape=circle,draw] {}
node at ( 0,1) [shape=circle,draw] {}
node at ( 0,0) [shape=circle,draw] {}
node at ( 1,1) [shape=rectangle,draw] {}
node at (-1,1) [shape=rectangle,draw] {};
\end{tikzpicture}
\section{ Exemplo 2          }


\begin{tikzpicture}[domain=0:4]
\draw[very thin,color=gray] (-0.1,-1.1) grid (3.9,3.9);
\draw[->] (-0.2,0) -- (4.2,0) node[right] {$x$};
\draw[->] (0,-1.2) -- (0,4.2) node[above] {$f(x)$};
\draw[color=red]    plot (\x,\x) node[right] {$f(x) =x$};
\draw[color=blue]   plot (\x,{sin(2*\x r )}) node[right] {$f(x) = \sin x$};
\draw[color=orange] plot (\x,{0.05*exp(\x)}) node[right] {$f(x) = \frac{1}{20} \mathrm
e^x$};
\end{tikzpicture}

\section{Exemplo 3}

\begin{tikzpicture}[domain=0:4]
\draw[very thin,color=gray] (-0.1,-1.1) grid (3.9,3.9);
\draw[->] (-0.2,0) -- (4.2,0) node[right] {$x$};
\draw[->] (0,-1.2) -- (0,4.2) node[above] {$f(x)$};
\draw[color=red] plot[id=x]      function{x}           node[right] {$f(x) =x$};
\draw[color=blue]   plot[id=sin] function{sin(x)}      node[right] {$f(x) = \sin x$};
\draw[color=orange] plot[id=exp] function{0.05*exp(x)} node[right] {$f(x) =
\frac{1}{20} \mathrm e^x$};
\end{tikzpicture}

\section{Conclusions}

\bibliographystyle{plain}
\bibliography{jj}

\end{document}

