Find the directional derivative of the function at Point P in the direction of u or V as appropriate. 263 . f ( x , y ) = xy , P ( 0 , - 2 ) V = bit 3 j 273 . f ( x , y , 2 ) = 4 2 + X Z P ( 1 , 2 2 ) V = 5 2 - 1, 27 Find the gradient vector at the indicated Point 293 . fly 4 , 2 ) = x Jy 2 + 2 2, P (- 2, -15-1) Find the desiative of the function 297. f ( x , 4, 2 ) = In ( xy+ yz+ Zx ) at point ( - 9 , 18 , - 27 ) in the direction the function increases most rapidly