@machamppoke,
You need to differentiate once and equate the result to zero in order to establish (solve equation) for turning points (maxima and minima etc) .
You then need to differentiate a second time and establish whether the second differential coefficient is +ve (indicating a minimum) or -ve (a maximum) at the turning points, or equal to zero (for a point of inflection).
Stumble It!
Tweet This
Bookmark on Delicious
Share on Facebook
Share on MySpace