Champaign, IL
6/28/2010
The seedling of this whole chalky project was born when I walked past a parking ramp at Colorado and 9th in Austin, Texas. The multiple-storied wall of this ramp is covered in 4 or 5-foot square squares of cement. It looks like enormous graph paper. I have this dream of putting some sine and cosine graphs on that ramp.
On this fine day in late June, though, I was sitting outside a bakery in downtown Champaign and the sidewalk was this lovely grid. I refused to walk away without leaving a little periodic function.
As you may know Sine and Cosine are intimately related. The “co” in “cosine” references “complementary.” Complementary angles add up to 90 degrees—put them together and you have a right angle. If you get yourself a right triangle on a flat (Euclidean) surface, then the two acute angles are complementary. The sine of one of those cuties is the cosine of the other, and vice-versa.
The point is Champaign’s new (but temporary) sinusoid (wavy) graph could be either sine or cosine.
Footpath Math: Chalk it up to a math geek 
sweet!
math = beautiful