Casey's Angle
- Author:
- Maurice OReilly
John Casey (1820-1891)
To celebrate the bicentenary of the birth of John Casey on 12 May 1820, this applet illustrates Casey's angle, BOC = B'O'C'.
12 points are shown here, 7 large and 5 small. Move the seven large ones as you will to explore Casey's angle.
How can you accurately describe what you observe?
For more information about Casey, his work and, in particular, his angle, check out Peter Lynch's That's Maths in the Irish Times of 7 May.
Pauline Romera-Lebret situates Casey's work on 'new triangle geometry' in the context of teaching geometry in Europe and the USA in Dig where you stand, Reykjavik, 2009.