I apologize if I am repeating this message, however, I think that I incorrectly posted the message the first time. I am using this text as a compliment to the text used in my class. I have been working my way through the problems in chapter 1. I have run into troubles on 1.56, and 1.61. Would it be possible for anyone to post the derivation of these questions, thus enabling me to establish where I am making mistakes?

Thanks

Colin, NY