Find the work done by the force field F(x,y) =
<2xy-cosx,ln(xy)+cosy> along the path C, where C starts at
(1,1)(1,1) and travels to (2,4)(2,4) along y=x^2, then travels down
to (2,2)(2,2) along a straight path, and returns to (1,1)(1,1)
along a straight path. Fully justify your solution.