Another find of the FEM study is Octave, a great Math package.
Octave is a reimplementation of part of Matlab developed by Professor John Eaton at the University of Texas, Austin, and later at the University of Wisconsin, Madison.
If you are looking for an Open source alternative to Matlab you should give Octave a try.
The Finite Element Method, its basis & fundamentals, O.C. Zienkiewicz, R.L. Taylor, J.Z. Zhu, 6th edition ISBN 0-7506-6320-0.
Studying the Finite Element Method, I ran into a booklet with some math exercises, Exploratory Examples – for Real Analysis, by J.E. Snow and K.E. Weller, ISBN 0-88385-734-0.
Just for the fun of finally using OOO formulas ;-), I created this OOO calc document for exercise 1.2.
Again the FEM study leads to unexpected interesting stuff, such as Sage, a wonderful Math package. If you want to explore Math and you are not (yet) prepared to buy Maple or Mathematica, start with Sage.
It also helps with your ‘homework’ for The Theoretical Minimum, “what you need to know to start doing physics” by Leonard Susskind and George Hrabovsky.