A particle free to move along the xaxis has potential energy given by u(x)=k[1 exp(x)] for +infinite to infinite, wherekis a positive constant of appropriate dimensionsthen(a) at point away from the origin, the particle is in unstable equilibrium(b)for any finite nonzero value of x, there is a force directed away from the origin(c) if its total mechanical energy is k/2, it has its minimum kinetic energy at the origin(a) for small displacements from x = 0, the motion is simple harmonic​