The displacement (in meters) of a particle moving in a straight line is given by
s = t^2 - 4 t + 18,
where t is measured in seconds.
Find the average velocity over the time interval [3,4].

Question

agreene · Answer

$$v(t) = r'(t)$$
$$V _{AVG} = V _{f} - _{i}$$

So, take the derivative of your displacement vector and then plug in your initial and final times for t, subtract initial from final (t=4 - t=3)

agreene · Answer

$$V_{AVG} = V_{f} - V_{i}$$
For clarity.