1. The problem statement, all variables and given/known data http://img337.imageshack.us/img337/3014/classicalmechs.jpg [Broken] I'm fine until showing that those 4 things are constants. 2. Relevant equations dxj/dt=dh/dpj and dpj/dt=-dh/dxj 3. The attempt at a solution I can't show they are constant, for example, can someone show me where I'm going wrong here for p1-0.5bx2: d(p1-0.5Bx2)/dt=d(p1-0.5Bx2)/dxj*dh/dpj+d(p1-0.5Bx2)/dpj*(-dh/dxj) =-0.5B*dh/dp2+(-dh/dx1) =-0.5B(2p2-2eA2)+(eBp2+0.5e^2Bx1) I think I'm fine on the last part as long as I can assume the constants.