| ▲ | Pi square is nearly 10(mihai.page) | ||||||||||||||||||||||||||||
| 27 points by freediver 4 hours ago | 23 comments | |||||||||||||||||||||||||||||
| ▲ | olooney an hour ago | parent | next [-] | ||||||||||||||||||||||||||||
I like the 4-5-6 theorem:
Well, to five decimal places, anyway. Some other good ones:
There are also famous "almost integers" such as this one discovered by Ramanujan:
Which is is almost an integer to 12 decimal places. | |||||||||||||||||||||||||||||
| ▲ | lifthrasiir 3 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
The second fact, pi^2 ~= g, is famous enough that it has a separate section in Wikipedia [1]. [1] https://en.wikipedia.org/wiki/Mathematical_coincidence#Gravi... | |||||||||||||||||||||||||||||
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| ▲ | renyicircle 3 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
My first thought was "well of course it is, since pi is a little larger than 3" but it was cool to see an actual derivation of how much pi squared differs from 10 as a nice, closed form series. | |||||||||||||||||||||||||||||
| ▲ | verzali 2 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
I remember discovering that pi x 10^7 is very close to the number of seconds in a year while at uni. One of my tutors was convinced this had to be more than coincidence, but I always figured it was just chance and a nice but sometimes useful shortcut... | |||||||||||||||||||||||||||||
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| ▲ | leni536 2 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
This first became apparent to me when I got a slide rule. Pi is often marked on the various scales and an x^2 scale is often nearby the x scale. | |||||||||||||||||||||||||||||
| ▲ | awinter-py an hour ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
need a countdown for when it gets there | |||||||||||||||||||||||||||||
| ▲ | Dwedit 2 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
If you don't unblock scripts from cdn.jsdelivr.net.cdn.cloudflare.net, the math code won't work. | |||||||||||||||||||||||||||||
| ▲ | Lerc 2 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
I was a little disappointed that the upper range of gravity on earth only goes to 9.8337. Just a little more and there would have been somewhere on earth that was an exact match. It would have been the ideal (if chilly) place to start a cult. | |||||||||||||||||||||||||||||
| ▲ | amelius 26 minutes ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
Pi^0 is exactly 1. | |||||||||||||||||||||||||||||
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| ▲ | BrandoElFollito 2 hours ago | parent | prev | next [-] | ||||||||||||||||||||||||||||
As an ex-physicist, pi^2 is 10. Like g. I get it that this is a nice calculation with the Zeta function and everything, but 3 and a small something squared will be near 10 so it is 10. | |||||||||||||||||||||||||||||
| ▲ | smitty1e 3 hours ago | parent | prev [-] | ||||||||||||||||||||||||||||
The author wants tau=2*pi, but in the Greek alphabet, tau has one vertical stroke, and pi has two. So, visually in Greek, pi=2*tau would seem an improvement. Oh, well. | |||||||||||||||||||||||||||||
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