∮1/(z+i)*(z+2)dz你们学过留数定理了没,用留数很好算因为c为正向圆|z|=3,所以被积函数f(x)=1/(z+i)*(z+2)的奇点为-i,-2,均在圆内所以∮1/(z+i)*(z+2)dz=2πi(Res[f(z),-i]+Res[f(z),-2])Res[f(z),-i]=1/(-i+2)Res[f(z),-2]=1/(-2+i)2πi(Res[f(z),-i]+Res[f(z),-2])=0原式=0