I'm trying to find the minimum and maximum values of
on the surface of
I have already put
Getting the following 4 equations... Where do I go from here?
Since the value of is not part of the solution, I often find it best to eliminate first by dividing one equation by another.
Dividing the first equation by the second gives or so .
Dividing the third equation by the second gives so .
Putting x= -2y and z= -3y into the last equation gives a single equation for y.