sorry, I should have been more specific. the cone is of uniform density and the axis of rotation is through the apex and the center of the base. I think I found the way for triple integration, but the single is a little different. I think I am to find the area of anyone of the right triangles...
I am supposed to prove the moment of inertia about a spinning cone through the diameter. but I am supposed to do it using single integration and triple integration. I think I did it right in the triple integration but I really don't know what needs integrating with the single. the paper gave...