With the exercises you can check whether you understood the lecture. There will be always three exercises. The first should be an easy application of the theory. The second is a bit more challenging. The third is more difficult and only to show that the topic has considerable depth. For the examination you need only to be able to do the first and second exercises.
It is nevertheless interesting to try the third exercises.

There will answers of the first and second exercises, one week after they are given.