144 MATHEMATICAL FORMULA AND ELLIPTIC FUNCTIONS 



+ + --- . = 1.54308. 



4- ~_\e- --) = 1+1 + ^ + . . . . = 1.175201, 



O * * 



if i\ 



[. -le - -} 

 2\ ej 



5. cos i = i --+-.,... = 0.54030. 



6. sin i = i J + . . . . = 0.84147. 



o * o * 



6.921 



4 



, 



"~ " 



2 . __,_! + ! ._! + . 

 10 3 2 3 4 3 6 



16 ii i 



3 " ^ = ~ 4 2 + 4 4 ~ 4 6 ^ 



25 i,i i 



6.922 ^ 2 ^ = e ~" + e " 9r + *~ 21?r + J T(i) = 3.6256 



6.923 (Special cases of 6.705) : 



