二重积分分步积分。先对dy积分。y的上限是x,下限是x^2∫[sinxy/x]dx=∫(sinx-xsinx)dx=[-cosx+xcosx-sinx] x的上限是1,下限是0-cos1+1*cos1-sin1-[-cos0-sin0]=1-sin1 (2):圆锥体的体积:∫∫∫dxdydz=∫∫[z]dxdy z的上限是x^2+y^2,下限是0=∫∫(x^2+y^2)dxdy化为极坐标∫∫r^3dθdr=[r^4/4][2π]=8π