The function is  and the interval is .

Apply derivative on each side with respect to .

Quotient rule of derivatives : .

Power rule of derivatives: .

To find the critical numbers of , equate  to zero.

are in the region .

To find the absolute extreme of function in given region , sketch the function .

Critical point is minimum point over the interval .

Critical point is maximum point over the interval .

Minimum point is   .

Maximum point is .