Hi, I'm preparing for my calculus II final and I had a question about Power Series. I'm posting the link for the answer solution to a practice exam (it's in pdf form) and I will ask questions based on that. http://www.math.sunysb.edu/~daryl/prcsol3.pdf On problem 12 it asks for the fifth derivative, I'm not sure why they did the last part. I can do the first three steps and solve for the power series of f(x) but I have no clue why they do that last part so if you can clear it up it would be appreciated. On problem 7 part F...can you please explain the rules for limit comparison theorem. Also, when facing a problem like that, what series are good to use in comparison to the series given to you? Thanks for any help, more questions will be asked in the future...heh.