posted by Anonymous .
find the acceleration at time t=9s if the position (in cm) of a particle moving along a line is s(t)=6t^3-7t^2-9t+2 at time t.
V(t) = dS/dt = 18t^2 - 14t -9
Acceleration = dV/dt = 36t-14
Plug the value of "t" in the above and that's the answer