The acceleration of the car three seconds before it comes to a stop is 0m/s²
Given the velocity function expressed as v(t) = -3t^2 + 18t + 9
Acceleration is the change in velocity of a body with respect to time.
a(t) = dv/dt
Differentiating the velocity with respect to time will give;
dv/dt = -6t + 18
a = -6t + 18
a = -3(6) + 18
a = -18 + 18
a = 0m/s²
Hence the acceleration of the car three seconds before it comes to a stop is 0m/s²
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