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.

(In reply to Improved Solution by Harry)

Don't worry about the compass.

Any construction that can be done with straightedge and non-collapsing compass can be done with straightedge and collapsing compass - it just takes more operations.

Posted by Bractals on 2010-01-13 16:58:34