A weight is attached to a spring suspended vertically from a ceiling. When a driving force is applied to the system, the weight moves vertically from it equilibrium position. This motion is described by the model y = 1.5sin8t - 0.5cos8t where y id the distance from equilibrium in feet and t is the time in seconds. Write the model in the ofrm sqrt(a^2+b^2)sin(Bt+c)