Question 8 Co/1 pt ) 3 0 Details Find a unit normal vector to the surface f(x, y, 2) = 0 at the point P(4, 1, - 24) for the function f(x, y, z) = In 4y Please write your answer as a vector (a, b, c) with a negative z component, and show your answer accurate to 4 decimal places n = Question Help: Video Submit Question Determine if a function is differentiable. Use the book's definition of "error term" (@ link ) . Question 9 Go/1 pt ) 3 0 Details The definition of the error function also defines an "error term" E(r, y). Find E(x, y) for the function f(x, y) = - 5x2 - by at the point (1, - 1). Hint: See the definition of Differentiation in the textbook (link to textbook) Submit