A force parallel to the x-axis acts on a particle moving along the x-axis. This force produces potential energy U(x) given by U(x)=αx^{4}, where α=0.630J/m^{4}. What is the force (magnitude and direction) when the particle is at x = -0.800 m?

^{4}, where α=0.630J/m^{4}. What is the force (magnitude and direction) when the particle is at x = -0.800 m?