A mass of 250 g stretches a spring 1.568 cm. If the mass is set in motion from its equilibrium position with a downward velocity of 20 cm/s, and if there is no damping, determine the position u of the mass at any time t.
Enclose arguments of functions in parentheses. For example, sin(2x).
Assume g = 9.8 m/s^2. Enter an exact answer.
u(t) = _____ m