Solutions to exercises have been updated

Solutions to exercises have now been updated with solutions from chapter 2 and 3. 

One of you had a print of the introduction to convexity, in which there was a small difference in the numbering of the exercises. This was a version from the beginning of the semester in which I had made one change: Exercise 3.17 in the old version was renamed to exercise 4.7 in the new version. This resulted in a change of the numbering of the succeeding exercises.

?yvind