§. pracccdcnti dcmonrtraiiimii<; 



z. ^^ rArc.cor/^-^"^-^ -Arc.cof. ( L^L^'\ 



z^e'—i/'-'L \iH-fcof.(p/ Vi-t-f-col.Cpy 



Vi-t-fcol.Cp i-»-fcol.(pvJ 

 ct fecflor hyperboliciis Q, radiis vedoribus f, ^•' angulo \|/-v|>'' 

 comprehcnlus 



= ^ ' rArc.cor.f^^-" ^"^•^VArc.cof.f ^^-^"^-^^ 



2 ',?-'— i/='L Vi-^rcor.\i.y Vi-^^'cof.v|/7 



-^-.i/(.'-i)f_j!^li:!__ ^"-^'-^ \]. 



\i-Hf col.vjy i-t-tcol.v/J' 

 hincque colligitur omnino ob ~t— ~ -rf—; P : Qr y p : yp\ 



§. 20. Qucmadmodum in Elementis Trigonometriac 

 dcmonftratur cdc : 



cof. (a -h p) = cof. a cof. p — fin. a fin. (3,- 

 fin. (a -H |3; =:: fin. a cof. ^ -|- coC. a fin. |3,- 

 cof. (a — (3; :=r col". a cof. (3 -f- fin. a fin. (3,- 

 fin. (a — ^)~ fin. a cof. (3 — cof a fin. (3 ; 



ita quovjuc pro hypcrbola aequilatcra dcmonltrabitur, eflc : 

 C.(a-t-p) = C.a C.(3 -I- S. a S. (3i 

 S. (o£-4-|3) =1 S. a C. (3 -f- C. a S. P; 

 C. (a— ^) z= C. a C. (3 — S. a S. ^ ; 

 S.(a — P) m S.a C.j3 — C.a S. (3; 



vnde colligitur 



C.''a-i-p) -i- q.ra— ,3) =: 2 C.a C. f3; 

 C.(a-t-(3) — Cra — p; — 2S.aS.p; 

 S.(a-|-p)H-S.(a— (3) = 2S.aC.(3; 

 S. (a— (3) — S. ^a— (3) n; 2 C. a C. f3 ; 

 Ko:/^ ACta AcaJ. Imp. Sc. 7. /. Y tumque 



