POLYGONORVM RECTILINEORVM. 



121 



fi enim pon;Uur 



^g^fin. jF/ 



(e-\-d^aa.B-c hn.Cj(f+/'/-« lin.B-K liu.C)— "' ^ » 



prodibit 

 b+acol.B+ccoi:.C-coCGVie+ii+aCm.B-cCw.C]ic+d-a^i^3+cCin.Cy 



Simili fere rationc ex lecunda exprcfiioiie dctenri- 

 nutur latus a^ tumque ex Ttrauis elici pott-ll e. 

 Si quaerendus fit angulus E, ilia acquatio : 

 ^ed{in.{E'=iie-{-dy-{a{\n.B~cCin.C)'-ib+acoiB-{^co(.Cy 

 commode adhiberi poteft , nam fi ponatur 



f?) _*_ • cof. 



B-4.cid/.cL — fin. H' , fiet 



(^ _^ df — ,^jjn. B — cjm. C;« 



4^ ^lin. i E':=((^-|-^/-(^fin. B - <r fin. C)*) cof. H\ 



Vt au^em ex aequatione hac (ecunda eliciatur angir- 



lus B, fiat euolutio termiaorum hunc angulum in- 



\olaontium , \t fit 



V4-2 f ^coi. E-t-/zifl'-i-Z>*+/+ 2 ^^cof C+ 2 tf cof. B [b+ccoCC) 



— 2aciia.B.Cm.C. 

 lam quaeratUT 



Tang.K:^^-i^-^-, eritque /^*+/+. J.cof. 0-^,^^ 



Vnde cnnfequimtir 



^'+ c f ^cof E 4-^' - «' +'=^^^'1!^+ 2 «f g-f cof (B -f- K) , 



Iiinc fit 



(<H-<'_4r^fin.iE'z(rt-l^?)'+4fli|;:;;^cof'(R4-K)*ct 



(r-^ '+4^^cof i v:- {a + j;;; •^'^j- 4 « t-^-^^ ^''^- * (^ ^ ^^''» 



cx quibus iundim lumtis coUi^itMr 



Tang ;(B4-K) zz li -^ — -, 



ie+d;^[a-y^)-^td[in.lE" 



lom.XX. Nou.Comm. Vl ^^^^^ 



