a point mass is constrained to move in a horizontal plane and is attached to four fixed pegs by 4 light springs. The four pegs are arranged at the corners of a square of side root2*a. Each spring has a natural length of a/2 and a spring constant a. If the mass is displaced towards one corner through a small distance d<<a and is then released from rest, what is the angular frequencyof this SHM? So far I have tried to resolve forced in x and y direction but that didn't work. This seems to be quite tough. Thanks for any hints.