1. The problem statement, all variables and given/known data Use Lagrange multipliers to ¯nd the maximum and mini- mum value(s), if they exist, of f(x; y; z) = x^2 -2y + 2z^2 subject to the constraint x^2+y^2+z^2 2. Relevant equations 3. The attempt at a solution Basically after I find the gradient of the functions I get this. 2x=2x lamda -2=2y lamda 4z=2z lamda. One case lamda equals 1 while the other it equals 2. Does this mean that the Lagrange Mult can't be used?