The Elements of Euclid : viz. the first six books, together with the eleventh and twelfth : the errors, by which Theon, or others, have long ago vitiated these books, are corrected, and some of Euclid's demonstrations are restored : also, the book of Euclid's Data, in like manner corrected (1806)
Euclid, Simson, Robert, 1687-1768, Euclid. Elements. Book 11-12. English. 1806, Euclid. Data. English. 1806, Simson, Robert, 1687-1768. Notes, critical and geometrical. 1806, Simson, Robert, 1687-1768. Elements of plane and spherical trigonometry. 1806 · Philadelphia : Published by Mathew Cary, and sold by J. Conrad & Co., S.F. Bradford, Birch & Small, and Samuel Etheridge, printed by T. & G. Palmer ... · leaf 87
PROP. XXL THEOR. THE angles in the same segment of a circle are Sec nequal to one another. Let ABCD be a circle, and BAD,BED angles in the same segmentBAED: the angles BAD, BED areequal to one another. Take F the centre of the circleABCD: and, first, let the segmentBAED be greater than a… … 86 THE ELEMENTS Booklll. the circumference, viz. BCD, for their base; therefore the an-*>—-v—^ gle BFB is double » of the angle BAD: for the same reason,a 20.3. the angle BFD is double of the angle BED: therefore the angle BAD is equal to the angle BED. But, if the segment BAED be not greater…
Euclid's Elements · Mathematics, Greek · Geometry
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![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-186-102.webp)
