(a) Find if . Do not simplify your answer.

(b) Find .

(a)

(b)

[6] 2. Find if . Do not simplify your answer.

Set . Then .Differentiate implicitly to get . So

[6] 3. Show that the function increases for .

First we find: . We now see that for . So increases for .

[5] 4. The function has critical points at and at (do not check this). Use the second derivative test to check which of these two values yields a local minimum.

;

Since we have a local maximum for at the point .

Since we have a local minimum for at the point .