Do not trust problem set answers

[corvi42]

Just to let you know, I've already caught 2 errors in the answers to just one of the problem sets, and had these confirmed by Joel, so if you're studying from the problem sets beware!!!!  

The answers given are not necessarily right - if you get something different from what they have there and you're positive you're right, then you might be.  Mind you the problems I found were minor - having negatives in the wrong place.  The numbers came out right, but were the wrong sign.  Anyway, just a heads up to the rest of you to watch for this.  ;D  

[TheSearchIsOn]

Yeah I know what you mean. I found a few errors here and there as well. And even though I've shown them to some TAs they haven't been corrected in the solutions.