Hi, I'm working on exercise 9.13 of the "bible" Gravitation. The problem I have is how to derive the following equation:(adsbygoogle = window.adsbygoogle || []).push({});

[itex]R_x(t)R_z(\psi)R_x(\theta)R_z(\phi) = R_z(\psi-tsin\psi cot\theta)R_x(\theta+tcos\psi)R_z(\phi+tsin\psi/sin\theta)[/itex]

Where [itex]R_x(t)[/itex] denotes an infinitesimal rotation about x-axis, i.e. t<<1. [itex]R_z(\psi)R_x(\theta)R_z(\phi)[/itex] denote three consecutive FINITE angle rotations about z, x, and z axis, with Euler angles [itex]\psi[/itex], [itex]\theta[/itex] and [itex]\phi[/itex] respectively.

Can anyone help me on this? Thanks!

In case the latex doesn't work, I attach the equation below

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# Need help on an exercise from Gravitation(MTW)

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