1. The problem statement, all variables and given/known data I had to calculate an orbital speed for an arbitrary density ρ(r) I got: V = r*sqrt(G*ρ(r)*4π/3) 2. Relevant equations I am supposed to leave this in integral form, which I don't know how to do as I do not understand calculus. ρ(r) is density of r, hence the calculus required Please help me transform this in integral form. If you could solve it for me too, that would be amazing! Thank you so much!