证明如下: Ms2ndL1Ws,nr、L v 2 ArE 28 2 l ArE Firu 1 Wr s nid= 2A282(x Are hi=iu+ id Wr s 2 L LArp: 8 Sw Ara ps L 8 2 ArE g 2 S 2 2 2 S=8(1+2)-琪其中:u=证明如下： a Lw s s s w s a L s Ara L w s g LAr g ArE L w s g Wr i iu id ArE L l r w s g Wr ArE Firu L id ArE L l r w s g Wr ArE Fird L iu p s s = + − = = = = = + = = = = + = = −             ) 其中： 2 (1 2 2 2 2 2 (1 ) 2 2 1 2 (1 ) 2 2 1 2 2 2 2 2 2 2 2 2 2 2 2