5 ms·
No, the tau manifesto agrees: radius is the more fundamental concept. That's why tau is better! Pi is an expression relating the diameter to the circumference
by blahedo 14y ago
No, the tau manifesto agrees: radius is the more fundamental concept. That's why tau is better! Pi is an expression relating the diameter to the circumference, which as you point out is a little counterintuitive.
- Retric 14y agoThe problem with tau for introductory math is area = pi * r^2 = (tau/2) * r^2. Given the choice between having equations with 2x or other with 1/2 y most people feel more comfortable with 2x. EX: e^(i * tau / 2) = -1 wait what?
- bascule 14y agoIf you read the Tau Manifesto you'll see why tau * r^2 / 2 is actually AWESOME (he actually refers to it as pi's coup de grace) Just think of it like an integral (that's what it is, after all!), raise the power and divide by the power. Suddenly the origin of this formula is no longer obscured. Regarding Euler's identity: e^(i * tau) = 1
- deleted 14y ago[deleted]
- Retric 14y agoTelling a 3rd grader to think of it like an integral seems to be putting the cart WAAAAAAAY before the horse. Edit: Also that's is hardly a more fundamental equation because you could also say e^(1024 pi * i) = e^(4096 * tau * i) = 1.
- bascule 14y agoIt won't amaze third graders, but it would make a lot more sense the first time you learn integral calculus
- Retric 14y agoMeh, so did 2 * pi * r > 2 * pi * (r ^ 2) / 2 = pi * r ^ 2. The great thing about math is it's it works out either way. So, it really comes down to which is easier to deal with and students seem to have an easier time remembering and understanding 2pir and pi*r^2, but in the end it's tau day so that's what people want to argue about.
- bascule 14y ago"students seem to have an easier time remembering and understanding 2 pi r and pi r^2" Are you speaking from empirical experience as a math teacher? What makes 2 pi r easier to understand than tau r?
- fryguy 14y agoAlso perhaps, make integral calculus make more sense?
- waterhouse 14y agoEh, 3rd graders can probably handle the area of a triangle, which can be viewed as a definite integral. (Somehow, middle school physics students seem to be able to handle computing the distance traveled by an object given starting velocity and constant acceleration--again, technically an integral.) In fact, one can view a circle as being made up of a bunch of really thin triangles (this is how one usually derives the area of a circle), and this again is something that third-graders can appreciate--cut a paper circle into slices, and see if you can get the slices to look more and more like triangles as you cut them smaller. (I vaguely remember doing something like this in elementary school.)
- aidenn0 14y agoWe should thus not teach anyone the formula for area of a triangle then
- Retric 14y agoThe area of a triangle does not have both a constant and a division by 2.