I'm making a model of a sine wave out of popsicle sticks. Essentially I'm digitizing a sine wave. Let's say I'm modeling half of a cycle with ten sticks. So I need to know how long to cut each stick. So I figured it would be cos(arcsin(x/10)) for x=0 through 9. Wrong! I still can't figure out what the problem is, so I printed out a sine wave and traced it onto the sticks. That worked, of course.