Simple template to doing homeworks, with a header for Institution Image, important info, and a few libraries to do math stuff like tikz
\documentclass[12pt]{article}
\usepackage[main=spanish, dutch, english]{babel}
\usepackage[utf8x]{inputenc}
\usepackage{fullpage}
\usepackage{euscript}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[amssymb]{SIunits}%voor grootheden
\usepackage[pdftex]{graphicx}%voor figuren
\usepackage[colorlinks=true, linkcolor=blue, urlcolor=blue, pdfborder={0 0 0}]{hyperref}
\usepackage{graphics}
\usepackage{eurosym} %voor het euroteken
\usepackage[version=3]{mhchem} %voor chemische reacties
\usepackage{enumerate}
\usepackage{epsfig}
\usepackage{tikz}
\usetikzlibrary{babel,arrows,automata}
\usepackage{listings}
% \begin{lstlistings} [language=<language>]
% accepted languages: ABAP, ACSL, Ada, Algol, Ant, Assembler, Awk, bash, Basic, C#, C++, C, Caml, Clean, Cobol, Comal, csh, Delphi, Eiffel, Elan, erlang, Euphoria, Fortran, GCL, Gnuplot, Haskell, HTML, IDL4, inform, Java, JVMIS, ksh, Lisp4, Logo, Lua, make, Mathematica, Matlab, Mercury, MetaPost, Miranda, Mizar, ML, Modelica, Modula-, MuPAD, NASTRAN, Oberon-, Objective C , OCL, Octave, Oz, Pascal, Perl, PHP, PL/I, Plasm, POV, Prolog, Promela, Python, R, Reduce, Rexx, RSL, Ruby, S4, SAS, Scilab, sh, SHELXL, Simula, SQL, tcl, TeX, VBScript, Verilog, VHDL, VRML, XML, XSLT.
\title{Tarea 3}
\makeatletter
\let\thetitle\@title
\makeatother
%hoofding voor de taak, niks aan veranderen
\newcommand{\hoofding}[6]{
\begin{flushleft}
\includegraphics[height=3.2cm]{Logo_Uchile_modern.png}
\end{flushleft}
\vspace{-3.6cm}
\hspace{4.5cm}
\parbox{8cm}{ #1\\Curso : #2\\
Codigo : #3\\Fecha : #4\\
Autor : #5\\ Mail : #6\\}
\hspace{2.3cm}
{\parindent=0pt \hrulefill} %lege regel invoegen want moet als paragraaf gezien worden
\vspace{5mm}}
%einde hoofding van toetsen
% invocar figura
\newcommand{\figuur}[2]{\includegraphics[width=#1]{#2}}
%hiermee is er geen insprong bij een nieuwe alinea
\setlength{\parindent}{0pt}
%de witruimte tussen twee alinea's wordt iets groter
\setlength{\parskip}{1ex plus 0.5ex minus 0.2ex}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
%naam,klas,nr,datum,vak,leerkracht
\hoofding {\thetitle}{Teoría de la Computación}{CC3102-1}{\today}{Bastián}{mail@gmail.com}
% Titulo, si se quiere
%\begin{center}
%\LARGE{\textbf{Titel}}
%\end{center}
%Documento
\input{contents}
\end{document}
\end{document}