三、二重积分的性质 1fx,No=kjfx,do(k为常数 2jL/x,)±g(x,Na =J八Dfx)do±∬gx,y)dg 3对于任何常数α,B,都有 [a财x)+s(xdg=nfx,)do+nx)do 4.J∬nfx,yda=八x,)do+,fx,)do (D=DUD2,D1,D2无公共内点) BEIJING UNIVERSITY OF POSTS AND TELECOMMUNICATIONS PRESS 目录上页下页返回结束目录 上页 下页 返回 结束 三、二重积分的性质 D 1. k f (x, y)d ( k 为常数) 3.对于任何常数α,β,都有 = D k f (x, y)d + = + D D D [f (x, y) g(x, y)]d f (x, y)d g(x, y)d D 4. f (x, y)d = + 1 2 ( , )d ( , )d D D f x y f x y