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# Title: Où il répond à plusieurs difficultez qui luy ont esté proposées sur la Dioptrique, la Geometrie, & sur plusieurs autres sujets (shelfmark Leibn. Marg. 43:3)
# Folio 308, page id 82327652X:0336
# Original at the GWLB: https://digitale-sammlungen.gwlb.de/resolve?id=82327652X&page=336
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# Model: FoNDUE-GD_v2_ft_Leibniz, run 74, 2026-09-06T16:05:13Z — 52 lines, status machine
# Lines: 52 recognised, mean confidence 0.85
# Machine transcription. Not an edition. Errors are expected: about 8% character error rate on Latin and French lines, higher on German.
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18
L IRES
au lieu de Parabolen, e atos HI ne Faudra pas changex vA
+Lo
MCME.
Raisonnement par lequel aLonsieur de Fermat precend
trouver la tancente de la Parabole.
IE dara parabole B D N, cuius verrex D, diame: ex
DDC, ec punctum in ca datum B, ad quod ducenda est
recta BE, tangens parabolen, ex in punctoF, cum diame.
troconcurrens; Frgo lumendo quodlibet punctum in recta
BF, e ab co ducendo ordinatam OI, a puncto aurem B,
ordinatam B C, majorerie
Proporrio C D ad D I,
quam quadrati B C, ad
quadracum OI. Ouia pun-
ctum O eA exera parabo-
len. Sed proprer similitu
dinem criangulorum, ue B
Cquadracum, adOIqua-
dracum, ita C P quadra
cum ad I F quadratum;
Major isieur erie propor-
tio C D, ad D I, quam
quadrari C F, ad quadra-
cum IF. Cum aurem pun-
ctum B decur, datur appli-
cara B C; Ergo punctum C. Dacureriam C D. Sicigitur
CD, aqnalis D dacx. PONAEUF C F esse A. POnatuF C P,
eAC F. ErgoD, ad D - P, habebiemajorem proporrionem
quam Ag, ad Ag F F g - A in P bis. Fc ducendo inter sC
medias _C CxEreMAS, D in A g + D in F g - D in A in F bis,
majus erie quam D in Ag = A g in F. Adaequeneur igieur
juxca Cuperiorem methodum. Dempris itaque communibus,
D in F. g - D in A in F bis, adaequabiEuE = A g in F, aUE
quod idem est, D in E q Y Ag in E, adaequabitur D in A
seul moc en tout le reste, comme on verraicy manifecte
de D
M
d
bis
idem
et
ation
murbes
Plus
Van
erana
au
axpli
0
d