1. The problem statement, all variables and given/known data Write the cartesian equations of the movement of a material point of mass m that is in a forces field in which the potential energy is V(x,y,z)=-αy^2 , and you know that at time t=0 the point is in the position which has coordinates (0,0,Z0) with velocity v=V0*j P.S: Sorry for my bad english but i had to translate it because it was an exercise of an exam at Mechanical Engineering at University of Bologna, Italy 2. Relevant equations I can't understand how i can solvec this kind of prblem ? How should i think? I heard that it's something with differental equations write ? 3. The attempt at a solution Sincerely don't know where to start.