A spring of length 10cm, suspended from the ceiling by a small mass, is stretched by 5cm and released. Its acceleration at t seconds after the release is a(t) = —20 cos (2t) cm/s ² (the negative sign indicating acceleration back toward the equilibrium point). Using only the material up to and including Section 5.1, estimate the distance it has travelled after two seconds, using right Riemann sums with n = 8. Your final answer should involve exact values rather than estimations (i.e. NO calculators) and it should not involve absolute value bars.

Instead of using the Fundamental Theorem, refer to Sections 4.9 and 5.1 where appropriate. Do NOT use the Fundamental Theorem of Calculus.