As the name suggests, I invented this theorem. My theorem is as follows:

1. When an angle is inscribed in a semicircle, it is a right angle.

2. AB is the diameter of circle C. Draw the perpendicular bisector of AB intersecting circle C at a point (not labelled).

3. Make the angle bisector of angle ADB. It intersects the circle at the same point as the angle bisector in "step 2"

Click here to return to Ian's Geometry Forum.