I need to differentiate D (the first equation). In this equation, there is an arcsin. I am not sure what to do about this. Well . . . just have a look: http://www.mlowery.0nyx.com/differentiate.jpg If the browser says access denied, copy and paste the URL into a new browser window and it will work. I do not know whether or not I used the chain rule correctly and I have never differentiated arcsin before. Yes, this is part of my homework. But it is a small part of a larger project. I know exactly what I have to do to complete the project. I have just spent 3 hours attempting to differentiate this. Please do not assume I am simply trying to get a free answer.