为自己加油

把下列曲线积分化为相应的二重积分，其中C是平面区域D的正向边界：
(1)∮_C(1-x²)ydx+x(1+y²)dy；
(2)∮_C(e^xy+2xcosy)dx+(e^xy-x²siny)dy.

(1)∮_C(1-x²)ydx+x(1+y²)dy =∫∫_D[1+y²-(1-x²)]dxdy=∫∫_D(x²+y²)dσ (2)∮_C(e^xy+2xcosy)dx+(e^xy-x²siny)dy =∫∫_D[e^xy•y-2xsiny-xe^xy+2xsiny]dxdy =∫∫_D(y-x)e^xydσ