An object moves according to the law s = t2 + 5t - 8. What is the average rate of change of s with respect to t in the interval t to (t + △ t) ?

The average rate of change can be calculated as:

Mavg = (((t+∆t) ² + 5 (t+∆t) - 8) - (t² + 5t - 8)) / ∆t = (∆t² + 2t∆t + 5∆t) / ∆t

= ∆t + 2t + 5

So, the average rate of change is: ∆t + 2t + 5