Hello killer786

Welcome to Math Help Forum!The function has a maximum value when and a minimum value when Since there are multiple maxima and minima, there will be multiple values of and . Below, I've taken the first (and most obvious) values.

So varies between and . Since these maximum and minimum values are 8 and 2 respectively, we get:The maximum occurs when . So, from what I said above, the simplest value is:

The minimum is when . So:

(1)

So the formula we want is:

, from (1)

and

Grandad