( 278 ) 

 To intcgi-ato C3 we add to this integral : 



— n (3— «^) I V ~ — -^ tun-^ z . dx , 

 wbicli ai'terwards will l)e subtiMcted from Do. So Cj becomes : 



Ci —-n (3—rr} ~ y ^ <«" ^ ~ • £?•' 



But now we find : 



4^2 



]/ d.c = d V{x-^/i) i-i-n^) , 



x'" x—n'' X J 



so that we get (the varions developments — as was said before — 

 will be published elsewhere) : 



Cg' = —n {'i—n~)\— —V(j;~Hi) (.i— n-) tnu-^ z — 



Likewise to the integral C.^ is added : 



2 f 1/ ''-ILh ia, -1 n: . dx , 

 J x—n- 



whieh shall direetly bo subtracted from D^. For 



C.' — 2 I 5 K ^ tan 1 «c . (/,(• 



J x^ x—n- 



we find in (luite the same way as for Cj' : 



r4C,. 1/1 



Ci — 2 -^^ — l^ix—^li) {x—n"~) tan-^ nz + 



L a; 



+ 2 « - ^ — 2 ia«-i ~ + -^ <««-' V2 --'J . (S) 



