Step 1:

Sum rule of derivatives : .

Step 2:

To find the critical numbers of , equate to zero.

for .

for .

not in the region.

Critical points in the given interval are .

So the test intervals are , and

Step 3:

Intervals	Test Value	sign of	conclusion
	\ \		increasing
	\ \		decreasing
	\ \		increasing

Extremes :

If on an open interval extending left from and on an open interval extending right from , then f has a relative maximum at .

If on an open interval extending left from and on an open interval extending right from , then f has a relative minimum at .

Solution :

Maximum =

Minimum=

Intervals	Test Value	sign of	conclusion
	\ \		increasing
	\ \		decreasing
	\ \		increasing