Let f(::} be a C1 function oft with f't) # 0. (a) Put F(x, 3.!) 2 fax? + yz}. Find the gradient VF at an arbitrary point and Show that it is parallel to the straight line which joins the point and the origin. (13) Put Glix, y) = f(y/x). Find VG at an arbitrary point whercx ;E U, and Show that it is orthogonal to the straight line joining that point and the origin