Problems

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Found: 3

The isosceles trapeziums ABCD and A1B1C1D1 with corresponding parallel sides are inscribed in a circle. Prove that AC=A1C1.

From the point M, moving along a circle the perpendiculars MP and MQ are dropped onto the diameters AB and CD. Prove that the length of the segment PQ does not depend on the position of the point M.