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 255
. DC : H,; therefore(11. 5.) COS. BC : cos. liD : : cos. AC : cos. AD, and alternately, cos.BC : cos. AC II cos. BD : cos. AD. Q. E. D. PROP. XXVII. The same construction remaining, the sines of BD, DAthe segments of the base are reciprocally proportional tothe tangents of B and A, the angles at…
Euclid's Elements · Geometry · Trigonometry
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
