44^ Opuscula . 
lem ponere, fietque binomii reciprocum aff — bgg X/v^ 
"^^gg — ^ff ^g^"^"» quod divifum per rationale quantum 
aff — hggi ^Sii f\/ a — g\/bi notiflimum binomii /v/J-f-^/^ 
reciprocum . 
XVU. Si formula data > prxter radicalia , terminum 
quoque habeat rationalem , in affumendam quaefiti iilius re- 
ciproci formulam omnia radicalia admitienda funt, qux ex 
datis in formuia expofita radicaiibus componi poiTunt , ejuf- 
dem indicis ac radicaiia data , & praeterea terminus ratio- 
nalis, & deinde fupputatio inftituenda eft , ut fuperius di- 
^lum eft de formula » cujus omnes termini fint radicalia ; 
ducendo nimirum aifumptam reciproci formulam in expofi- 
tam , & fingulos terminos , qui idem radicale habebunt in 
hoc fado, nihilo adsequando ; terminum autem ejufdem fa- 
£ti rationaiem feponendo , tamquam inutilem ad Invenien- 
dos valores coefficientium , quibus unumquodvis ex radicali- 
bus afflcitur in formula affumpti reciproci . Formula ergo 
affumenda pro inveniendo reciproco dats formulx /vVtf -h 
g\/b-\-Ci ubi c eft rationale, quantum erit K\/ a -^^lfh 
D)/aa-{- EVhb-h F 4- G \/aab H \/afb -h K\/aabb 
HrR. Odo coefficientia fingulos terminos irrationales muU 
tiplicantia 5 & quantum ipfum rationaie R requirenda funt, 
ducendo hanc affumptam formulam in expofitam , & odo 
terminos , qui hoc dudu oricntur, ( fepofito termino ratio- 
xiaii ) nihilo adaequando * 
XVIIL His tamen exemplis do<5li intelligimus curan- 
dum efie, ne fuperflua radicaiia in formularum pro recipro- 
cis inveniendis aiTumptione accipiantur, fed formulx, quan- 
tum id fieri poteft , fimplices flatuantur ; cavendum vero 
ett in formularum afifumptione , ne in illis defit radicale 
quodpiam ex iiiis, qux non fupeiflua , fed necelTaria funt 
ad formijlx complementum ; nani luperflui quidem termini 
incommodo & labori funt analyitx, verum formulam nul- 
latenus vitiant ^ at fi qui defint ternnni in aflumpta formu- 
la , reciprocum, quod quxrimus, ex illa nancilci minime 
polTumus . Dabimus itaque rationem inliituenda: formula: 
pro datarum formularum reciprocis, in qua termini neque 
redundcnt, r.eque deficiant. 
XIX. 
