QUESTION 4 Find the directional derivative of the function f (x,y ,z) =3x2ye - at (1,2, 1) in the direction of the vector 2 3 Round your answer to four digits after the decimal sign.the directional derivative of the function ,y ,z ) =3x2ye - at (1,2,1) in the direction of the vector 2 IN nd your answer to four digits after the decimal sign. 3 3 3