°(p2+) 当然这个积分也可以用留数定理作,有兴趣的同学可以尝试一下。 V2-=-4xo6(r) 三、习题 v(ar) 鉴于V×F=0 ax(Vxr) ax(V×f)=V(a,f)-(aVF V(af)=4=4e1=4 =a v(x(axr))=v( ar-r(ar) Vra-V.(aF Vr2,a=}.a= v [F(a F)]=V, [F(ar)+var [F(ar)I =(af)(V·f)+[v(af)]产 3(a,f)+a,F=4a V·(F×(a×r)}=-2r.a 1.7 V.E sin(kF-o=V(k aE sin(kF- ak·r =kEo cos(k- F-or)( ) ( ) 2 5 0 2 2 3 3 2 2 0 12 1 12 1 4  d         = − + = − + = −  当然这个积分也可以用留数定理作，有兴趣的同学可以尝试一下。 2 1 4 ( )r r  = −  三、习题 1.1   = (a r) ? 鉴于  =r 0 =   + a r ( ) ? a r a r a r   =   −  ( ) ( ) ( ) ( ) j j i i ij i j i i a r e A r Ae Ae a   =  = =  = 1.1 ( ( )) ( ( )) ( ) 2 2 r a r ar r a r r a r a r    =  −  =   −       2 2 2 r r r a a r a r r    =  =   ( ) ( ) ( ) ( )( ) ( ) 3 4 ( ) r a r r a r r a r r a r r a r a r r a r r a r a r a r      =    +                =    +        =  +  =     = −  (r a r r a ( )) 2 1.7 ( ) ( ) ( ) ( ) 0 0 0 sin sin cos E k r t E k r t k r k r k E k r t      −    − =          =   −