As usual I did this question I'm working on backwards, doing the section dealing with air friction first. Now realizing I must do the 'first part' and I think I am over thinking again. With no air resistance, I need the position of a trajectory from Newton's second law. I know gravity is the only force I'm considering, so I start with: -mg = ma right? My prof said when I integrate I'll get combos of sin and cos... I haven't been able to get that.. am I doing something wrong? What steps should I take to integrate this properly? Thanks!