Ball, W. W. Rouse (Walter William Rouse), 1850-1925 · London, Macmillan and Co., limited · leaf 70
nd is perpendicular to it, we have the angle ODA equal to the angle OAD . Hence the angle ADG (which is the difference of ODG and ODA) is equal to the angle DAE (which is the difference of OAE and OAD). But ADO is a right angle, and DAE is necessarily greater than a right angle. Thus the result is… … acute, and that the angle A is greater than the angle G . From A draw AD making the angle BAD equal to the angle 0, and cutting BG in D. From A draw AE perpendicular to BG. The triangles ABG , ABD are equiangular; hence, by Euc. vi. 19, A ABG : A ABD = AG2 : AD2. Also the triangles ABG, ABD are of…
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Internet Archive · University of Illinois Urbana-Champaign · Public domain (published before 1931). Free to use for anything.
