Timeline for Polynomials with rational coefficients
Current License: CC BY-SA 2.5
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Dec 9, 2010 at 22:15 | comment | added | Hailong Dao | @Wadim: (-: That's a good use of MO. | |
| Dec 9, 2010 at 4:40 | comment | added | Wadim Zudilin | Hailong, I used your solution as the hardest problem in my number theory class (to show that your $f(x)$ is injective). Two students (of 16) could do it. | |
| Dec 9, 2010 at 4:37 | vote | accept | Wadim Zudilin | ||
| Jul 29, 2010 at 21:06 | comment | added | Jonas Meyer | $x^3-2x$ also works. | |
| Jun 6, 2010 at 10:35 | comment | added | Harry Altman | Also, this solution can be quickly tweaked to have integer coefficients; if there are no rational solutions to $x^2+xy+y^2=5/4$, then there can't be any to $x^2+xy+y^2=5$, either. Hence $x^3-5x$ also works. | |
| Jun 6, 2010 at 10:15 | comment | added | Harry Altman | I'm surprised this was possible with just a cubic. | |
| Jun 6, 2010 at 9:52 | comment | added | Wadim Zudilin | This is a very nice counter example for $n=1$! | |
| Jun 6, 2010 at 9:39 | history | answered | Hailong Dao | CC BY-SA 2.5 |