Elements of geometry : containing the first six books of Euclid, with a supplement on the quadrature of the circle, and the geometry of solids : to which are added, Elements of plane and spherical geometry (1826)
Playfair, John, 1748-1819, Euclid · Philadelphia : Marot & Walter · leaf 214
F; therefore, the angle ABC isto four right angles as the arch AC to the whole circumference ACF- Cor. Equal angles at the centres of different circles stand on arch-es which have the same ratio to their circumferences. For, if theangle ABC, at the centre of the circles, ACE, GHK, stand on… … DEFINITIONS. I. If two straight lines intersect one another in the centre of a circle,the arch of the circumference intercepted between them is calledthe Aleasure of the angle which they contain. Thus the arch ACis the measure of the angle ABC. II. If the circumference of a circle be divided into…
Euclid's Elements · Geometry · Trigonometry
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