Parametrization by arc length of Descartes Folium

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I have just learned what parametrization by arc length is and trying to gain some intuition on it I have tried to parametrize some curves. Lines, circles and helixes are easy using the following theorem (from my notes):

Let $\alpha:I \rightarrow \mathbb{R}^3$ be a differentiable (in this context $\alpha \in C^\infty(I)$) and regular curve. Then for each $a \in I$, $s:I \rightarrow J=s(I)$, $s(t)=\int_a^t||\alpha'(u)||du$ is a diffeomorphism. Furthermore, the curve $\alpha \circ s^{-1}:J \rightarrow \mathbb{R}^3$ is parametrized by arc length.

I found Descartes folium as an interesting example to apply this new theorem. My attempt is as follows:

$\alpha:(-1, +\infty) \rightarrow \mathbb{R}^3$ given by $$\alpha(t)=\left(\frac{3t}{1+t^3}, \frac{3t^2}{1+t^3}\right)$$ is the folium. From here, $$\alpha'(t)=\left(\frac{3-6t^3}{(1+t^3)^2}, \frac{6t-3t^4}{(1+t^3)^2}\right)$$ Clearly, $\alpha$ is differentiable, and equating both numerators to $0$ we see that there is no $t \in (-1, +\infty)$ such that $\alpha'(t)=0$. Using the theorem for $a=0$ we get that $$s(t)=\int_0^t 3\frac{\sqrt{x^8+4x^6-4x^5-4x^3+4x^2+1}}{(1+x^3)^2}dx$$ is a diffeomorphism, and we are looking for its inverse. However, the integral looks complicated and finding its inverse probably too. Is there any other way to do this?

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There is no other way. There is simply no closed form for $s(t)$ and its inverse.

At least you could use the Joukowsky transform $u(t)=t+\frac1t$ to get $$s_j(u)=3\int_{u(t)}^\infty\frac{\sqrt{u^4-4u-6}}{(u^3-3u+2)\sqrt{u^2-4}}\,du$$ but ultimately this doesn't help anything since it's a hyperelliptic (degree-$6$) integral.

Your best option is just to numerically integrate and invert $s$ to get the arc length parametrisation.