Key to the classification of problems :
- Trivial : If you can't do these, you are in trouble. Go study hard!
- Practice : You may do these for practice; at least do the underlined ones.
- Extension : These will extend your knowledge beyond what is given in the text or lecture.
- Challenging : You may do these for challenge. Try especially the underlined ones.
- Starred (*) : These are interesting.
- In paranthesis: Do one of these (they are more or less equivalent), sometimes explicitly written.
Read (and understand) the "Pitfall Prevention"s in the margins of the book.
It is also a good idea to read the examples, since they are already solved...