Fall2017 14 Partial Derivatives: Problem 21 Previous Problem Problem List Next Problem (1 point) Find the directional derivative of f(z, y, z) 4zy + z2 at the point (1,-1, 5) in the direction of the maximum rate of change of. (1,-1,5)-Du f(1,-1,5) = Preview My Answers Submit Answers You have attempted this problem 0 times You have unlimited attempts remaining.