Science:Math Exam Resources/Courses/MATH105/April 2012/Question 05 (b)/Hint 1

Recall the definition of the gradient:

$\nabla H(x,y)=\left\langle {\frac {\partial H}{\partial x}}(x,y),{\frac {\partial H}{\partial y}}(x,y)\right\rangle$

To use part (a), write H in terms of F and G.