The displacement (in meters) of a particle moving in a straight line is given by s = t2 - 8t + 18, where is measured in seconds.
(a) Find the average velocity over each time interval:
(i) [3, 4]
(ii) [3. 5, 4]
(iii) [4, 5]
(iv) [4, 4, 5]
(b) Find the instantaneous velocity when t = 4.
(c) Draw the graph of as a function of and draw the secant lines whose slopes are the average velocities in part (a) and the tangent line whose slope is the instantaneous velocity in part (b).