Suppose that 2 ≤ f '(x) ≤ 5 for all values of x. What are the minimum and maximum possible values of

f(6) − f(3)?

...?

Verified Answer :

For the answer to the question above.
If the maximum possible slope is 5 then the f(x + 3) =  5 x 3 + f(x)
So the maximum number for this is 15 and the minimum is 6 for this equation.
I hope my answer helped you in any way.