Stage: 4 Challenge Level: 
No solution yet with a good explanation
biology. chemistry. physics. Stage 5 Investigation. Investigations. engineering. Topology. Maths in STEM. Trigonometric functions and graphs. Learning through exploration.
Published November 2007,December 2007.
Copyright © 2007. University of Cambridge. All rights reserved.
NRICH is part of the family of activities in the Millennium Mathematics Project, which also includes the Plus and Motivate sites.
email: nrich@damtp.cam.ac.uk