Timeline for Two circles and a pentagon
Current License: CC BY-SA 4.0
13 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 11 at 15:35 | comment | added | Oscar Lanzi | That does not work well for me. Copying and pasting wrecks tge formatting, which forces me to a lot of retyping and causes new errors. | |
| Apr 11 at 15:30 | comment | added | Alex Ravsky | @OscarLanzi A simple solution of this problem which usually fits is to delete an old comment and post a fixed or updated comment instead. | |
| Apr 11 at 15:00 | comment | added | Oscar Lanzi | I meant $\sqrt{\frac15(5-2\sqrt5)}$ but did not spot the error, which involved missing a \ character, within the comment time limit. I am strongly opposed to this time limit and have complained about it multiple times on Meta, with nonpositive results. | |
| Apr 11 at 14:41 | comment | added | Trunk | @Oscar Lanzi Tidy your MathJax a bit. $\tan{18} = 1 / \sqrt{5 + 2\sqrt{5}}$ | |
| Apr 6 at 17:35 | comment | added | Pranay | +1. This is essentially the same as the answer I had. I want to wait a bit more to see if there’s an answer with no calculations, but if none appears, I’ll accept this one. | |
| Apr 6 at 4:09 | comment | added | Oscar Lanzi | Alternatively: the tangent of 18° has the exact radical form $\sqrt{\ frac15(5-2\sqrt5)}$. Through algebra this is less than $1/3$ iff $\sqrt5>20/9$. Then $5=400/80$ and $(20/9)^2=400/81$. | |
| Apr 5 at 18:47 | comment | added | Alex Ravsky | @xnor I updated the answer. | |
| Apr 5 at 18:45 | history | edited | Alex Ravsky | CC BY-SA 4.0 |
added 383 characters in body
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| Apr 5 at 18:08 | comment | added | xnor | Is there a way to see the trigonometric value is less than 1/3 without plugging it into an calculator? | |
| Apr 5 at 6:59 | comment | added | Alex Ravsky | @quarague Done. If you need more details, feel free to ask. | |
| Apr 5 at 6:58 | history | edited | Alex Ravsky | CC BY-SA 4.0 |
added 267 characters in body
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| Apr 5 at 6:48 | comment | added | quarague | A little more detail on your computation would be helpful. | |
| Apr 5 at 4:47 | history | answered | Alex Ravsky | CC BY-SA 4.0 |