my try on problem2 was take the partial devaritive eaqual to zero, get the C.P. then take the boundary point (3,2) , to find the max and min. it that right?
also, how to do problem#4?
I would use Lagrange Multipliers on #4 . . .
4. Find the points on the curve of intersection of the surfaces: .
in that are closest to the origin.
We want to minimize: .
. with the constraints: .
We have: .
Take partial derivatives and equate to zero . . .
Then solve the system for: .