SOLIS CIRCA AXEM. a85 



Qiins biiias i.ncognitas iiidc dctcrmiiiari opor- 

 tct , qiiod tres dilhntiae %^M, "PM", S>M'' i"tcr 

 lc ucqu-.ilcs efle debcnt. 



VHRNAl tria triangula fphacrica ^^ tt AI , "^ tt M^ 

 '^ttW, ob angulos "^J tt M =r « -i-J' ; ^7rM^=;^+J' 

 ^TtiSV^ — i- -\-j dab u n t : 



cof ^13 M zz cof./. cof. ::: -f fi n ./. {m.z. cof (a -4-.> ) 

 co(>]>M^ zzcof.g.cor.^-+-ria.^ fin.c;.cof (Z'-+-j') 

 col. ^p M' ^ — cof h. cof. ^ -t- fm. Z?. fin. s. cof [c -\-y) 



ct cx triurti haruni formularum acqualitate confc 

 quimur ; 



cotangszr ^g-coj.j et ctiam 



f/-. ^ ro/. 'a -+- :>} — r n. ft. co/. fc -f- ^i . 



cot.ing.c:— — ^— ^Tf 



hincquc porro : 



-\- { fm ./. cof g - fi n ./ cof b'coC. [a -\-y)'] 

 -\- (fin. g. cof i^ — fui. ^. cof./) cof «{ Z' +j') h =: o 

 -l-'fin.Z\cof /■— fin.Zrcof jg)cof i,f+/)i 

 ex qtia tamicm colligimus tang. j'n: 



-f cof a. nn/cof. g-cofZj^^-Fcof^.fing.^cof^-cofO-fcoftrfin./^fcof/^-cofg) 

 H-fin.tT.fin/cofg-col.Z^J-l-fin Z7.1in.g.(col.Zi-cof/j4-tm.t'.fin./:7(cof/-cof.g) 



hocquc valorc fubllituto cotang. c ~ 



fin. {b — a) fin./".fin.^.-l- fin. [f — b'' fin g. fin. b + fin. (a — c) fin./ fin b 



{Cin.f\oCg{co(.g-con.->)+coC{b-a^Xm/.i\n.g,co['.g-coi'.b\coi'.b-co('.f)'^ 



y 2'? fin g^cofZ? cof /;-cof/)-|-cof f-^jfin g.fin /'(cof/p-cof/) cof/^-cof^"! V 



Lfin./p'cof/(cof/-cofg)-|cof^<7-6\fin.Z:?.fin/(cof/-cof.g)(cofg-cof.Z;)J 



Nn .3 IN- 



