250 



Francisci Bertelli 



Et hie qiioque , ut in num. 5 , quantitas 

 j«'' — 2aa'cos(y,' — t', )-!-«' j~| evolvi poiestj ideoque fieri 



,(") T,(0 



' ^B -hB cos (n't — nt-*-e' — i) 



(6) )rt'»— 2aa'cos(n7— A»<-i-£'— e)^a! \~^=} 



,(2) 



B cosZ(n't — nt-*-£' — e) 



(3) 



B cos3(«'« — nt^e' — s) 



B cosi(n't — nt^e' — s) 



quae aequatio, si numerus integer i varietur intra terminos 

 — 00, -+-00, et sumatur 



(7) B(-0=B('), 



in banc contrahitur 



-I 



:.-^*'d«„ 



(8) ]a':i—Zaa'cos(n't—nt^e'—e)-*-a''] "2=^s B>''cosi{n't—nt^s'—sy, 



ubi coefficientes B^"), B^^^^ B^^)^ g(i)^ functiones sunt 



quantitatum a,a'. 



Tribuantur jam nunc incrementa «U, a'U'jV,V' quanlitati- 

 bus a,a',(^7it-^s),(n't-^e'); erit 



I [r.'2_2r.r,'cos(i;/-v,Kr.2J-|= i 



< -t-oo (0 I ' 



^ is B , „ cosi(n't—nt-He'—e^Y—\) ) 



\ —00 (a-(-aU,n -t-o U ) ^ ' ' 



ac proinde aequatio (/?') vertetur in 

 T 





m' 



(9) R=( (a'-na'U') 



/» 

 4 





