# Tagged Questions

Elementary questions about functions, notation, properties, and operations such as function composition.

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### Iterating a relation to find a function

I was playing around with a graphing calculator, trying to find approximations for inverses of $f(x)=x^5+x+1$. This cannot be expressed with radicals or the like, but I wanted to see how close I could ...
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### Prove a primitive recursive function

I'm supposed to prove that the division of integers (whole numbers) is primitive recursive. I know that the add, subs, mult are primitive recursive but I don't know if that helps, I'm not asking for ...
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### The function $f:X\rightarrow X$ is defined in such a way: $f(x)=x-\frac1x, f^{(1)}(x)=f(x), f^{(n)}(x)=f\left(f^{(n-1)}(x)\right)$

Let the set $X=\mathbb Q / \{-1;0;1\}$. The function $f:X\rightarrow X$ is defined in such a way: $$f(x)=x-\frac1x, f^{(1)}(x)=f(x), f^{(n)}(x)=f\left(f^{(n-1)}(x)\right), n\in \mathbb N.$$ Is ...