Roots of non-linear function with arbitrary power coefficient

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Consider the function $f: (0,\infty) \rightarrow \mathbb{R}$ $$ f(X) = \frac{X^n}{K^n + X^n} - \gamma X $$ where $n \in \mathbb{R}$ is an arbitrary power. Assume for simplicity that $1 \leq n \leq 2$, and also that $K > 0$, and $\gamma > 0$.

Why is it hard to find the (real) solutions to $f(X) = 0$ for general $n$? For integer $n$, i.e. $n=1, n=2$ we can obtain algebraic solutions, but the expressions are not very insightful, and for non-integer $n$ this does not seem feasible. Any reference to the type of equation this is or what field of mathematics studies solutions to such equations would also be helpful.

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Numerically we can solve for this equation and find between 1 and 3 solutions depending on the precise value of $n$, $K$ and $\gamma$. The first term is known as the Hill function and the overall the equation models gene expression with positive feedback (the first term) and degradation (the second term).

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Solving for $X$ : $$\frac{X^n}{K^n + X^n} - \gamma X =0$$ $$X^n-\frac{1}{\gamma}X^{n-1}+K^n=0$$ If $n$ is an integer and $1\leq n\leq 4$ the solution(s) are known on the form of the combination of a finite number of elementary functions. This is possible because some elementary functions such as Powers, Roots, etc. have been defined and are commonly used.

If $n=5$ the solution(s) can be expressed on the form of the combination of a finite number of elementary functions and special functions : Jacobi theta functions or some hypergeometric functions. This is possible because those special functions where defined and can be used.

To answer to the question raised: In the general case ($n$ not integer), this does not seem feasible because no convenient special functions are available for this use, up to now.