1. (16 pts) Find equations of the tangent plane to the surface x +y' +z' =2xyz at the point (1,2, 3). 2. (20 pts) At what point(s) on the ellipsoid {x + 2y + 4z =1 is the tangent plane parallel to the plane 2x + 2y+z=1?3. Let f (x, y) = y3 + 33ch2 6x2 6322 + 2 . (a) (20 pts) Find all critical points off (list as ordered pairs). (b) (20 pts) Use the second partials test to nd any relative extrema or saddle points of f . List the x ,y - , and z coordinates of those points