Math -- it's around us

I was over a friend's house tonight and something caught my eye. Math.This isn't something new to me, but this is the first time I thought to write about it.The shadow cast by the lampshade (which is a circle) from the bulb (think of it as a point source, though it's not) is a hyperbola.The cone of light cast by the bulb is, by definition, a cone. The wall in this case is looking at a slice of that light; a slice of that cone. That is exactly the definition of a hyperbola! You are looking at a section of a cone -- a conic section!:-)Math: It doesn't just work, it's all around us if you take a moment to look around.