Can someone tell me if i have done the following question correctly because according to the book's answers this is incorrect.
For the surface given
Find the stationary point or points and determine the nature of any such point.
because there is still i differential again
therefore i get saddle point according to the statement
Points (1,-4,-16) > 0 & g > 0
answers is (1,-2,-8) is a local minmum; (-1,-2, 8) is a saddle point
how do i find the minmum point?