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@JonathanPlasse
Last active March 22, 2020 17:26
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$$ M= \begin{pmatrix} -\sin 0 & -\sin \frac{2\pi}{3} & -\sin -\frac{2\pi}{3}\\ \cos 0 & \cos \frac{2\pi}{3} & \cos -\frac{2\pi}{3}\\ \frac{1}{3} & \frac{1}{3} & \frac{1}{3} \end{pmatrix}= \begin{pmatrix} 0 & -\frac{\sqrt{3}}{2} & \frac{\sqrt{3}}{2}\\ 1 & -\frac{1}{2} & -\frac{1}{2}\\ \frac{1}{3} & \frac{1}{3} & \frac{1}{3} \end{pmatrix} $$

$$ M^{-1}= \begin{pmatrix} 0 & \frac{2}{3} & 1\\ \frac{1}{\sqrt{3}} & -\frac{1}{3} & 1\\ -\frac{1}{\sqrt{3}} & -\frac{1}{3} & 1 \end{pmatrix} $$

$$ R(\theta)= \begin{pmatrix} \cos\theta & -\sin\theta & 0\\ \sin\theta & \cos\theta & 0\\ 0 & 0 & 1 \end{pmatrix} $$

$$ R(\theta)^{-1}=R(-\theta) $$

$$ \begin{pmatrix} v_{x0}\\ v_{y0}\\ L\omega \end{pmatrix}= R(\theta) \begin{pmatrix} v_x\\ v_y\\ L\omega \end{pmatrix}= R(\theta)M \begin{pmatrix} v_1\\ v_2\\ v_3 \end{pmatrix} $$

$$ \begin{pmatrix} v_1\\ v_2\\ v_3 \end{pmatrix} = M^{-1} \begin{pmatrix} v_x\\ v_y\\ L\omega \end{pmatrix} = M^{-1}R(-\theta) \begin{pmatrix} v_{x0}\\ v_{y0}\\ L\omega \end{pmatrix} $$

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