Full text: Barrow, Isaac: Lectiones Opticæ & Geometricæ

4. Conſequentèr in harum ſecundo gradu ſin & gt;_ c_; in tertio, ſi _n_ 3
& gt; _cc_√{_cc_/3} - {_cc_/3} √ {_cc_/3} = {2/3}_cc_ √ {_cc_/3}; vel _n_ 6 & gt; {@@/27}_c_ [?] 6 ; in quar-
to ſi _n_ 4 & gt; {_c_ 4 /4} - {_c_ 4 /16} = {3/16}_c_ 4 ; nulla radix habetur; unam in iſtis
caſibus recta EF curvas ſupergreditur; nec iis occurrit.

5. Itidem in his omnibus maxima poſſibilis radix eſt AH = AC.

6. Curva CYH eſt _Circuli quadrans_, reliquæ AMH, ANH
quodammodo κυχλο{ει}δ{ετ}ς.

7. Ad ſextam ſeriem pertinentium curva HLL eſt _byperbola æqui_-
_latera_, cujus axis AH; reliquæ ſunt _Hyperboliformes_. Unde quoad
hanc ſeriem liquent cætera.

88. Series ſeptima.

_a_ + _b_ + {_cc_/_a_} = _n_.

_aa_ + _ba_ + _cc_ = _nn._

_a_ 3 + _baa_ + _cca_ = _n_ 3 .

_a_ 4 + _ba_ 3 + _ccaa_ = _n_ 4 , & c [?] .

In recta BAH indefinitè protensâ capiatur AB = _b_; & in AD
ad BH perpendiculari ſit AC = _c_; ſint etiam anguli HAR, HBS Semi-
recti; tum arbitrariè ductâ GY ad AH perpendiculari quæ ipſam
BS ſecet in Y; fiat AG. AC: : AC. YK; & per K intra angulum
DVS deſcribatur _hyperbola_ KKK; ſint demum curvæ CLL, AMM,
ANN tales, ut inter AG (vel GZ) & GK ſit _media_ GL, _bime_-
_dia_ GM, _trimedia_ GN; hæ ſatisfacient negotio. Nam eſt GK = _a_
+ _b_ + {_cc_/_a_}; & GLq = _aa_ + _ba_ + _cc_; & GMcub = _a_ 3 + _baa_
+ _cca_; & GNqq = _a_ 4 + _ba_ 3 + _ccaa_.

88.1.

Fig. 214.

89. Not.

1. Secundi gradûs curva CLL eſt pars _hyperbolæ æquilateræ_, cujus
_centrum_ O, ipſam AB biſecans; & ſiquidem AC& gt; AO, eſt OH
(ad AB perpendicularis, &) = √ ACq - AO qejus _ſemiaxis_; ſin AC& lt; AO, ejus axis eſt OI = √ AOq - ACq. reliquæ
verò curvæ AMM, ANN ſunt _hyperboliformes_.

Waiting...

Note to user

Dear user,

In response to current developments in the web technology used by the Goobi viewer, the software no longer supports your browser.

Please use one of the following browsers to display this page correctly.

Thank you.

powered by Goobi viewer