Timeline for Are there any nonlinear solutions to $f(x+1) - f(x) = f'(x)$?
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
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| Jul 25, 2022 at 15:21 | comment | added | user44143 | Taking the real parts yields $$f(x)=\left(\frac{c}{\sin c}\right)^x\cos(cx),\ \text{ with }\ \frac{c}{\tan c}=1+\ln\left(\frac{c}{\sin c}\right)$$ and some possible values of $c$ are $7.46$, $13.88$, $20.22$. | |
| S Jul 25, 2022 at 13:44 | history | suggested | Oscar Lanzi | CC BY-SA 4.0 |
Didn't work, rollback.
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| Jul 25, 2022 at 1:05 | review | Suggested edits | |||
| S Jul 25, 2022 at 13:44 | |||||
| Feb 16, 2015 at 14:01 | comment | added | Yaakov Baruch | for example $t\approx 2.08884301561304+i7.46148928565426$. | |
| Jan 14, 2010 at 15:13 | comment | added | Gerald Edgar | And if you don't want complex solutions to the original problem, just take real and imaginary parts... they are also solutions. | |
| Jan 14, 2010 at 14:43 | history | answered | mnf | CC BY-SA 2.5 |