Let f be a function of two variables that has continuous partial derivatives and consider the points A(4,9), B(9, 9), C(4, 10), and D(10, 17). The directional derivative of fat A in the direction of the vector AB is 2 and the directional derivative at A in the direction of AC is 11. Find the directional derivative of f at A in the direction of the vector AD. (Round your answer to two decimal places.)
Show transcribed image textLet f be a function of two variables that has continuous partial derivatives and consider the points A(4,9), B(9, 9), C(4, 10), and D(10, 17). The directional derivative of fat A in the direction of the vector AB is 2 and the directional derivative at A in the direction of AC is 11. Find the directional derivative of f at A in the direction of the vector AD. (Round your answer to two decimal places.)