298105
Lect. XII.
IN ſuſcepto negotio progredimur;
quod ut (quatenus licet) decurte-
11_Praparati@_
_Communis_. mus, verbíſque parcamus; obſervetur, in ſequentibus ubique _line-_
_am_ AB _curvam_ eſſe (quales tractamus) quampiam; cujus _Axis_ AD;
huic applicatas omnes rectas BD, CA, MF, NG perpendiculares;
& ME, NS, CB parallelas eſſe; _punctum_ M liberè ſumi; _arcum_
MN indefinitè parvum eſſe; rectam α β curvæ VB, α μ curvæ AM,
μ ν _arcui_ MN æquales eſſe; ad rectam α β applicatas ei perpendicu-
lares eſſe. His præſtratis,
11_Praparati@_
_Communis_. mus, verbíſque parcamus; obſervetur, in ſequentibus ubique _line-_
_am_ AB _curvam_ eſſe (quales tractamus) quampiam; cujus _Axis_ AD;
huic applicatas omnes rectas BD, CA, MF, NG perpendiculares;
& ME, NS, CB parallelas eſſe; _punctum_ M liberè ſumi; _arcum_
MN indefinitè parvum eſſe; rectam α β curvæ VB, α μ curvæ AM,
μ ν _arcui_ MN æquales eſſe; ad rectam α β applicatas ei perpendicu-
lares eſſe. His præſtratis,
I.
Sit MP curvæ AB perpendicularis;
&
lineæ KZ L, α φ δta-
22Fig. 156,
157. les, ut FZ ipſi MP, & μ φ ipſi M Fæquentur; erît _ſpatium_ α β δ ipſi
AD LK æquale.
22Fig. 156,
157. les, ut FZ ipſi MP, & μ φ ipſi M Fæquentur; erît _ſpatium_ α β δ ipſi
AD LK æquale.
Nam _Triangula_ MRN, PFM ſimilia ſunt, adeoque MN.
NR
: : PM. MF. unde MN x MF = NR x PM, hoc eſt (ſubſtitutis
æqualibus) μ ν x μ φ = FG x FZ; ſeu rectang. μ θ = rectang. FH;
ſpatium verò α β δ minimè differt ab indeſinitè multis rectangulis,
qualia μθ & ſpatium AD LK totidem rectangulis, qualia FH, æ-
quivalet. unde liquet Propoſitum.
: : PM. MF. unde MN x MF = NR x PM, hoc eſt (ſubſtitutis
æqualibus) μ ν x μ φ = FG x FZ; ſeu rectang. μ θ = rectang. FH;
ſpatium verò α β δ minimè differt ab indeſinitè multis rectangulis,
qualia μθ & ſpatium AD LK totidem rectangulis, qualia FH, æ-
quivalet. unde liquet Propoſitum.