(a) Find the gradient of the function at P

(b) Find a unit normal vector to the level curve ƒ(x, y) = c at P

(c) Find the tangent line to the level curve ƒ(x, y) = c at P, and (d) sketch the level curve, the unit normal vector, and the tangent line in the xy-plane.

Transcribed Image Text:

f(x, y) = 9x² + 4y² c = 40, P(2, -1)