Evaluate the Gradient of F at the Point P $f ( x , y , z ) = x y ^ { 2 } z ^ { 3 } , \quad P ( - 1,3 , - 1 )$

Evaluate the gradient of f at the point P. $f ( x , y , z ) = x y ^ { 2 } z ^ { 3 } , \quad P ( - 1,3 , - 1 )$