计算对坐标的曲线积分∮C{[(x+y)dx-(x-y)dy]/(x2+y2)},其中C为圆周
x2+y2=a2,沿逆时针方向.
令x=acosθ,y=asinθ(0≤0≤√2π) ∮C{[(x+y)dx-(x-y)dy]/(x2+y2)} =∫02π{[-a2(sinθ+cosθ)sinθ-a2(cosθ+sinθ)cosθ]/a2}dθ =∫02π-1dθ=-2π
计算对坐标的曲线积分∮C{[(x+y)dx-(x-y)dy]/(x2+y2)},其中C为圆周
x2+y2=a2,沿逆时针方向.
令x=acosθ,y=asinθ(0≤0≤√2π) ∮C{[(x+y)dx-(x-y)dy]/(x2+y2)} =∫02π{[-a2(sinθ+cosθ)sinθ-a2(cosθ+sinθ)cosθ]/a2}dθ =∫02π-1dθ=-2π