— i83 — 



D oP . 



Jam notetur e.sse tag. — — . . Dp . At quomam 

 DP _= DO cos. ODP __ R sin. (A + _ C), sive etiam 

 DP __ 2 R sin. (4-+C) cos. (A + C) __ *__E31_*__ 

 sxve denique DP =1 V Qj. — r) (p — r), erit 



D r 



ex quo porro valore conficitur 



sin. D __; 



2r/(<7 — r) (f-f-r) 



pq — r(p — q; » 



COS. _i— ^_ rtf __ 9 ) • 



Tandem eodem modo , quo supra §. io. usi sumus , demonstra- 

 bitur fore 



rnQ t> p pqq—rr (pp+ gg) 



_Ub, _• tt>w-r-rr(pi>— M )' 



sin. B 



__ 2pqrVpp — rr 



■ ppqq-r-rr(pp-qq-) 



unde sequens* componitur expressio: 



5 -r- 2 p q r Ypp — rr (pq — r (_ — <?) — 2 rr) / 

 q j n /T) T\\ CH- (ppgg- r r (pp-+-gg)) 2 rYjg^rJTf -f- r) , - 



v. ^" ^ ~"" " („_ — »•<_ — q))(ppqq-r-rr(pp-qq) 

 Ad hanc igitur pervenimus aequationem: 



S-H (_ <7 — 7" (_>— _0 — 2rr) . 2 p qrYpp — rr> 



<-+-( pp gq — rr (pp-y-qq) ■ 2 r Y(q — r) (_>->-r). ^_ /_ -+- r 



(Pq — r(p — q)) (pp qq ■+• rr (pp—qq)) — ' p -+- q 



quae per y p -+- r divisa , sublatis fractionibus sequenti modo 

 se habebit: 



r:7nf-X^:^^k^^^^^-^ 



