而△Sk △O 71+Ex(x,y)+Ey(x, y)dxd y k +Ex(Sk,nk)+Ey(sk,nk)(Aok)xy f(x V,2)dS m∑/(5k,mk,2(5km) k=1 +2x2(k,m7k)+=y2(k,7)(Aak) m∑/(5k,1k(5k,1k (光滑) +Ex(5k, nk)+zv(sk, nk)(ok) x,1)4-2 D f(x,y,z(x,D))v1+Ex(x,y)+y(x,y)dxdy 学 HIGH EDUCATION PRESS 机动目录上页下页返回结束z x y z x y x y k x y x y 1 ( , ) ( , ) d d ( ) 2 2   + +  x k k y k k k xy 1 z ( , ) z ( , )( ) 2 2 = +   +    x k k y k k k xy 1 z ( , ) z ( , )( ) 2 2 +   +    x k k y k k k xy 1 z ( , ) z ( , )( ) 2 2 +   +    f x y z x y z x y x y x y Dx y ( , , ) 1 ( , ) ( , )d d 2 2 = + +  ( , , ( , )) k k k k f   z   ( , , ( , )) k k k k f   z     f (x, y,z)dS 而 (光滑) 机动 目录 上页 下页 返回 结束