The tests will not require the use of MATLAB, although you will be allowed to use it. This may be hard to believe giving how much you use MATLAB in the homeworks, but in fact we are stressing MATLAB a bit more right now because we can use it to explore the concepts until we get enough formalism set up to do things a bit more analytically. For the midterm, we want to test your understanding of the concepts, not your ability to use MATLAB.