腔内介质的微扰 矢量循环公式 a·(b×C)=b·(c×a)=c·(a×b) (E0×H)=H·(×E) ·(E×Hn)=Hn·(n×E (35-13)矢量循环公式 (35-13)          a (b  c) = b (c  a) = c (a  b) b  a  c   ( ) (  )  ( ) (  ) * * * * n E H H n E n E H H n E   =     =                0 0 0 0 一、腔内介质的微扰