Find all the equilibria of the system

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Consider the system

$$\begin{align} \dot{u}&= v\\ 147\dot{v}&=8150-588v-20000w\sin{u}\\ 330\dot{w}&=-135w+85\cos{u}+61 \end{align}$$

Find all equilibria where each $u,v,w\in[-\pi,\pi]$.


I can't see a nice way to solve this since there are no common terms in the second and third equation. There is also nonlinearity present which makes the resulting equations harder to solve.

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equilibrium is when $$\begin{align} 0&= v\\ 0&=8150-588v-20000w\sin{u}\\ 0&=-135w+85\cos{u}+61 \end{align}$$

so:

$$\begin{align} 0&= v\\ 0&=8150-20000w\sin{u}\\ 0&=-135w+85\cos{u}+61 \end{align}$$

$$\begin{align} 0&= v\\ 8150&=20000w\sin{u}\\ 135w&=85\cos{u}+61 \end{align}$$

$$8150*135/20000=(85\cos{u}+61)\sin{u}\\$$

$$8150*135/20000=85/2\sin{2u}+61\sin{u}\\$$

this one last you need to solve for $u$ by some numerical method (I don't see a simple solution) and fill the number back to the second equation for isolated $w$. $v$ is obviously zero.

You can get the two solutions on wolframalpha.com