Wei Jian, I hope you will not be offended that I pointed out a mistake in your hw4 solution. The thing is: it's a very common mistake and I would like to make sure everybody learns not to make it. Would you mind leaving your solution as is so everybody can learn from it? --Mboutin 12:55, 23 September 2008 (UTC)
I just graded the solution of the practice midterm you just post. Great job and thanks very much for sharing. I hope you will find my comments helpful . --Mboutin 10:02, 22 October 2008 (UTC)
