Here's an upload of the question, we haven't really covered this material in class
a) My log-like = -a*n ln (b+xi) - n*ln Γ(a) + n*(a-1) ln yi - (yi/(b+xi))
I can get dl/db, but not dl/da
b) I get the solution b=-xi, but that doesn't seem right. I cannot get a solution for a.