Barrow, Isaac, Lectiones opticae & geometricae : in quibus phaenomenon opticorum genuinae rationes investigantur, ac exponuntur: et generalia curvarum linearum symptomata declarantur

Page concordance

< >
Scan Original
281 88
282 89
283 90
284 91
285 92
286 93
287 94
288 95
289 96
290 97
291 98
292 99
293 100
294 101
295 102
296 103
297 104
298 105
299 106
300 107
301 108
302 109
303 110
304 111
305 112
306 113
307 114
308 115
309 116
310 117
< >
page |< < (41) of 393 > >|
23441 punctum Zinfra punctum M; erit tum recta PE major arcu PX;
11Fig. 27. unde arc PA. PE & lt; arc PA. PX: : PM. XZ - PM: :
PM.
XZ - EH: : PM. XE + XZ & lt; PM. HZ. & viciſſim
PA.
PM & lt; PE. HZ. Verum ut priùs) eſt PA. PM: : PE. HK.
ergò PE. HK & lt; PE. HZ; proptereáque HK & gt; HZ; rorſus
itaque liquet Punctum K extra curvam exiſtere.
Tota proinde recta
MKZ extra curvam verſatur;
& eam tangit ad M: Q. E. D.
In tranſcurſu hoc.
ad alias curvæ noſtræ paſſiones revertamur.
VII. Si tangenti cuipiam (ut ipſi MT) parallela ducatur quæ-
piam EF (à puncto nempe quopiam E in recta infra punctum T ſum-
pto) hæc curvæ occurret.
Si enim infra punctum M in curva ſumatur punctum quodlibet, &
22Fig. 28. ab eo duci concipiatur curvam tangens recta;
huic occurret tangens
TM infra ordinatam PM.
ergò recta EF eidem occurret; at curvam
priùs tranſiliat oportet.
ergò liquet Propoſitum.
VIII. Eâdem operâ patet, ſi punctum aſſumptum E puncto T,
&
vertici A interjiciatur, rectum EF curvæ bis occurſuram, tam ſupra
quàm infra contactum M.
33con. 1. 27, 28.
Operosè conniſus eſt _Apollonius_ hæc de _Sectionibus Conicis_ oſtendere.
Cæterùm ad penitus determinandos occurſuum locos _Specialis mo-_
_dus ſeu ratio motuum deſcendentis atq;
tranſverſi cognoſci debet_; tunc
eos _Analyſis_ ſtatim prodet.
IX. Si duæ rectæ quævis (HM, KN) ad curvam propoſi-
44Fig. 29. tam æqualiter inclinentur (hoc eſt æquales cum ejus ad occurſus tan-
gentibus (puta cum ipſis MT, NX) angulos efficiant) hæ extrorſum
divergent, ſeu ad partes EF productæ concurrent.
Nam ducatur ſubtenſa NM; hæc utiq; ſecundum antedicta cum
ipſa AZ conveniet, puta ad O.
Eſt ergò ang OMH & lt; (ang.
TMH = ang. XNK & lt;) ang. ONK. ergo ang. HMN +
MNK &
gt; 2 rect. ergò rectæ HM, KN concurrunt ad partes EF.
Limitandum eſt hoc, intelligendo pares angulos HMA, KNA ad
eaſdem partes veſari;
ſeu alterum alteri fore externum interno. alias
cotnrà eveniet.
X. Si fuerit recta HM _curvæ_ perpendicularis (hoc ejus tan-
55Fig. 30. genti MT) &
in hac ſumatnr quæpiam definita HM; erit HM mi-
66_Apoll. V._ 38.&c. nima rectarum omnium, quæ à puncto H duci poſſunt ad curvam.

Text layer

  • Dictionary

Text normalization

  • Original
  • Regularized
  • Normalized

Search


  • Exact
  • All forms
  • Fulltext index
  • Morphological index