Para o vestibular, eu estudei por uns videos da Khan Academy. São bem didáticos.
https://www.youtube.com/watch?v=hjvY1OhEFlE
https://www.youtube.com/watch?v=M_GfECI_ZDA
https://www.youtube.com/watch?v=-L9jQxPZI1U
https://www.youtube.com/watch?v=aoMOdXBMRY0
https://www.youtube.com/watch?v=1l97a7oAKEk
https://www.youtube.com/watch?v=hmNqQMlOOfc
