Zach Effman

 31 Function whose third derivative is itself. 8 Is there a reason of $\cos(11x)+\sin(11(x+1))\approx 0$ 7 Could we “invent” a number $h$ such that $h = {{1}\over{0}}$, similarly to the way we “invented” $i=\sqrt{-1}$? 6 Remainder when $x^{1000000}$ is divided by $x^3 + x +1$ in $\mathbb{Z}_2[x]$ 5 If $f(x)=x^2-x-1$ and $f^n(x)=f(f(\cdots f(x)\cdots))$, find all $x$ for which $f^{3n}(x)$ converges.

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### Questions (2)

 13 What's the minimal structure needed to define a notion of derivative? 4 Computing global monodromy of branched covering of Riemann sphere

### Tags (75)

 32 ordinary-differential-equations × 2 9 arithmetic × 2 31 derivatives × 2 8 real-analysis × 6 31 recreational-mathematics 8 abstract-algebra × 4 11 polynomials × 2 8 ring-theory × 2 9 linear-algebra × 6 8 trigonometry

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