Use Green's Theorem to evaluate CFdr\displaystyle \int_{{C}}\vec{{{F}}}\cdot{d}\vec{{{r}}}, where

F=x+3y,2x+y\displaystyle \vec{{{F}}}={\left\langle\sqrt{{{x}}}+{3}{y},{2}{x}+\sqrt{{{y}}}\right\rangle}

C\displaystyle {C} consists of the arc of the curve y=2xx2\displaystyle {y}={2}{x}-{x}^{{2}} from (0,0) to (2,0) and the line segment from (2,0) to (0,0).

 

Hint: Check the orientation of the curve before applying the theorem.