CORPORVAl RIGIDORVM. 253 



\bi anguH A7.a, B 2 ^, CTc qiiia inter fe aeqiu- 



les, promiicue adhiberi pcfliiiir. Porro binas harum 



forniularum intcr fe conibiuando obtincbimus : 



cof. A ^ -i- cof. B ^ =r 2 cof. A 2 cof B 2 ( I — cof A 2 a); 



cof. Ab — cof. B fl = 2 cof. C 2 fin. A 2 « 



cof.A^-+cof.Cflz=:2Cof.A2cof.C2(i-cof.A2^)^ 



cof C«-cnf A c— 2 cof. B2 fin. A Za 



cor.B^-l-cof.;CZ;3=2co(.E2cor.C2(i-coCA2tf) ; 



cof. B r— cof Qb—z cof A 2. fin. A 2 ^. 



Dcnique esrcgia illa hinc coUigitur proprictas , 

 quod fit 



cof. A^'— cof. Ba^ cof B/— cof Qf'— cof Qa— cof A^* 

 —4. cof. A2. cof» B2cof C2 fin. A2(/(i — cof A2fl) , 

 fiue 

 cof.2A^-cof 2B<x=cof2Bt-con2Ci'— cof.iCa-cof 2Ac, 



12. Si in \aIoribus fupra pro cof A^,. 

 cof B ^, cof A f, cof C (7, cof. B ^, cof C Z^ inuentis, 

 lcco cof A2, cof B2, cof C2, cof A2a et fin.A2« 

 fubflitunntur eorum valores per toi. A a, cof.Bi^, 

 cof. Ct; exprcfll , cofinus priorum iflorum arcuum, 

 quoquc per arcus Ao, BZj, Qc hnbcbuntur dcfiniti.. 

 Vt autem hoc ficiUus fiat , pon.imus 



€\n.lAa :zza,\ fin.iB^^ — [3; fin.lC^r^zzy , 

 ex quo colligitur 

 coLAZ-ylXl~--> cof B2=y«±^P • cof C2-y 2±fc?:, 



p-*-V-+-a «-»-^-1-7' a-t-p+V» 



tumque 



i-cof A2rt=a+(3 + y; fin.i A2«=:y«-±?^^ hinc 

 cof i B 2 ^ ~ yi-'^.r^-?-±Jp. et 



fin. A 2 fl — y (a -f- p V y) (2 - a - (3 - y). 



113 His 



