Legendre, A. M. (Adrien Marie), 1752-1833, Brewster, David, Sir, 1781-1868, Davies, Charles, 1798-1876 · New York, Wiley & Long · leaf 48
48 GEOMETRY. Scholium, At a given point A, only one tangent AD canbe drawn to the circumference ; for, if another could be drawn,it would not be perpendicular to the radius CA (Book I. Prop.XIV. Sch.) ; hence in reference to this new tangent, the radiusAC would be an oblique line, and the… … Two parallels intercept equal arcs on the circumference. There may be three cases. First If the two parallels are se-cants, draw the radius CH perpendicu-lar to the chord MP. It will, at thesame time be perpendicular to NQ(Book I.Prop.XX.Cor.L); there fore, thepoint H will be at once the middle…
Trigonometry · Geometry
Internet Archive · Wellesley College Library · Public Domain Mark 1.0. Free to use for anything.
![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-145-81.webp)
