1. The problem statement, all variables and given/known data Derive Newton's Law of gravitation using kepler's laws. 2. Relevant equations Kepler's law equations. etc. 3. The attempt at a solution l= r(1- e*cos(theta)) l- const. e- eccentricity Solving these equations using kepler's laws (r^2(d(theta)/dt), etc.) second time derivative of r = -4c^2/(lr^2) + 4c^2/r^3 subtracting centrifugal acc. (4c^2/r^3) from it I get Newton's law. But I don't know how the centrifugal acc. come here.