Rate of changes

Question

The cost in dollars of producing x units of a particular brand of notebook is C(x) = x²- 400.

1. Find the average rate of change of C with respect to x when the production level is changed from x = 100 to x = 102. Include units in your answer.
2. Find the instantaneous rate of change of C with respect to x when x = 100. Include units in your answer.

Answer 1

1. Average rate of change is calculated by change in y / change in x . Use the function provided to find the 2 y values and then solve for the "slope".
2. Instantaneous rate of change means the derivative. Find the derivative of the function then use x=100 as you input. Units should be $/notebook.