计算三重积分I=∫∫∫Ω(x+y+z)dxdydz,其中Ω是由平面x=2，y=2，z=2及坐标面所围成的闭区域．
I=∫02dx∫02dy∫02(x+y+z)dz =∫02dx∫02[2(x+y)+2]dy =∫02[4(1+x)+4]dx =[8x+2x2]02=24.
计算三重积分I=∫∫∫Ω(x+y+z)dxdydz,其中Ω是由平面x=2，y=2，z=2及坐标面所围成的闭区域．
I=∫02dx∫02dy∫02(x+y+z)dz =∫02dx∫02[2(x+y)+2]dy =∫02[4(1+x)+4]dx =[8x+2x2]02=24.
