4^4 MEMOIRES DE l'Académie Royale 



cof. (m -4- 2 q) z= cof. m cof. 2 q H^ /In. m fin. 2 ^ ; 



cof. (4« H;^ 3 ^y) = cof. m cof. 3 ^ zrp (in. m fin. 3 ^ , &<^' 

 Aiiifi 



cT =r: cof. m (coC. q ~\- cof. 2 /^ —H cof. 3 ^ — f- ."' 



H— cof. // ^^ -+- fin. m ^fin. ^ —H fin. 2 ^ — J— fin. 3 ^ 



-i- -H /^n- « ;7/'/ 



c'eft-à-dire , 



„ cof. m cof. y [ fin. ntj -^ fin. ( n -\- ^ ) q — fin. q ] 



~~~ fin. 2 ^ 



fm. m fin. f [ i -H cof. q — cof. n q — cof. (n ->r- i ) q'\ 



I — cof. 1 f 



c. Q. /■. r. 



PROBLEMEXIIL 



( 16.) Sommer la fuite S =r: fin. ^?h ± q )'^ — f— fin. 



//H ± 2^/ H- fin. ^/H -t- 3<7/ -f- 



fin. ^m ;^;^ « ^y' .' 



Solution. 

 On a (théorèmes V , 1 1 1 & /VJ, fm. fin ± 5?/ 



' cof. f i m -^ i-q) , cof. 2 m cof. i q 



î 2 a 2 



fin. I m fin. z y 



2 

 r / X u ' t:of. 2 m cof. 4 7 fin. 2 m fin. + » 



■fin. (m ± 2^y = . ZJ— H U-j 



' X 2 2 



, , 1 II I cof. 2 m cof (5 (7 . fin. 1 m fin. 6 » 



'iïn. //;/ rn: 3<7y -=^ ^ — f- —: 



Cn. ^//; ^^ nq)'' :zr 



On aura donc, 



cof. 2 m cof. ma fin. 2 m fin. 2 » » 

 1 1 i_,- 



— cofi 



