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(315) 1

Part of 1991 Tournament Of Towns

Problems(1)

TOT 315 1991 Autumn A S1 area of cyclic ABCD =1/2 (AC)^2 sin A, BC=CD

Source:

6/9/2024
In an inscribed quadrilateral ABCDABCD we have BC=CDBC = CD. Prove that the area of the quadrilateral is equal to (AC)2sin⁡A2\frac{(AC)^2 \sin A}{2}
(D. Fomin, Leningrad)
geometryareasCyclic