Question

How do you find the maximum value of `-3(sqrt(x-9) + 12)`?

Answer 1

maximum value: `-36`

Explanation:

You were probably intended to use derivatives, but here is a solution from a different approach.

Note that `sqrt(x-9) >= 0`

`hArr (sqrt(x-9)+12) >= 12`

`hArr -3(sqrt(x-9)+12) <= -36`