By far the most popular and well-stocked category of used instruments is our selection of guitars, where we've got a huge variety of all the big names. Used Gibson Les Paul, pre-owned Fender Telecaster and secondhand Stratocaster guitars are commonly found within these pages, waiting for their new homes with players and collectors.
22/7 is a pretty decent choice for teaching 11-year-olds about fractions that are close to pi. 355/113 would be better, if you think they can remember numbers that big. And approxRational is fun. Exercise for the interested reader: implement an inverse to approxRational.
The Area of a Circle and the Value of Pi. It is once again Pi Day (March 14 or 3/14 in USA date format). I would just like to point out that the fractional representation of 22/7 is better than the three digits 3.14 thus the date of July 22 could be Pi Day also. If you want many more fun Pi Day posts, here are a few. Yes, Pi is indeed awesome. The Area of a Circle. So you have a circle. What is the area of that circle? Surely everyone remembers that the area of a circle is: Where Pi (Ï) is of course the number and r is the radius of the circle. Where does this formula come from? One method of obtaining this equation is to integrate dxdy over the area of a circle. Well, you probably wouldnât want to do that in cartesian coordinates â but you get the idea.