Hi, so basically have been looking at http://en.wikibooks.org/wiki/Special_Relativity:_Dynamics#Momentum" and working my way through the maths for myself. However I have hit this point and can't get past it:(adsbygoogle = window.adsbygoogle || []).push({});

\begin{align}

u = \frac{v - u}{1-\frac{uv}{c^2}}

\end{align}

Which should be able to become:

\begin{align}

u = \frac{c^2}{v(1-\sqrt{1-\frac{v^2}{c^2}})}

\end{align}

I have tried and tried but can't seem to get it to work. Can anyone help me out on this one please?!

Thanks

James

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# Relativistic Momentum Help With Equation Reduction

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