Davies, Charles, 1798-1876 · New York and Chicago, A. S. Barnes and company · leaf 68
C and D draw thelines AB, BC, CD, and DA: thenwill ABCD be the required square. For, the four right angled triangles,AOB, BOC, COD, and DOA areequal, since the sides AO, OB, OC, and OD are equal, beinjjradii of the circle; and the angles at O are equal in eachbeing right angles: hence, the sides… … 68 GEOMETRY Problems Sch. If we bisect the arcs AB,BC, CD, DA. and join the points,we shall have a regular octagon in-scribed in the circle. If we againbisect the arcs, and join the points ofbisection, we shall have a regularpolygon-of sixteen sides. ^
Geometry · Plane trigonometry
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