(2)考虑x=L1y=L2z=L3 Ex=A cos k,xsin k, sink.z 0.1.2.3 aE x=li Ox 0口如k4=0区L=m团 y=L2口E!=0→smk2=0國=nz z=l3→E1=0smkl2=0 kL=pr u=e,>E,=A, sin k, x cos k, ysin kz u=E E2=A3 snkrxsin kv ycosk,z 再由V.E=0 kA,tk atk a=o（2）考虑 L1 x = L2 y = L3 z = 机动 目录 上页 下页 返回 结束 E A k x k y k z x x y z = 1 cos sin sin u = Ey u = Ez E A k x k y k z y x y z sin cos sin = 2 E A k x k y k z z x y z sin sin cos = 3 0 3 Ex z=L = sin 0 z = L3 kz L3 = kz L3 = p 0 2 Ex y=L = sin 0 ky L2 = y 2 k L n =  L2 y = 1 0 x x L E x =  =  sin 0 kx L1 = x 1 x = L1 k L m=  0,1, 2,3... m n p = 、 、 再由  E = 0  0 kx A1 + ky A2 + kz A3 =