The global extrema of a function on a closed interval are either calculus type local extrema in the interior of the interval or occur at the end points of the interval.

So first look at the solutions of:

these are the roots of , which are and , is not in the interval so we can ignore it, so now we need only consider

and

so the global minimum on is and the global maximum is and these occur when and respectivly.

RonL