P-P Situation 5:

 In Figure 14 is an arbelos. Use the button "Play", to explore the construction of radius   of the Archimedean circle in arbelos. Build another Archimedean circle with radius . By using logic functions of GeoGebra, prove that  (van Lamoen, 2014, p. 253). 

Worksheet “Archimedean circle in Arbelos”