Let L and N be adjacent cusps of a cycloid.
Let P be a point on the cycloid between L and N.

Construct with straightedge and compass the tangent line to the cycloid at point P.

It would be most unfair of me to offer a solution as I only really became aware of what was a "cusp", was told that L and N did not coincide, and that P is any point one cares to choose on the curve.

Yes, I know the solution, but it's not mine.

Posted by brianjn on 2010-01-04 23:56:22