(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

start from:

x = [x' + vt']/sqrt[1 - v^2/c^2]

ct = [v/cx' +ct']/sqrt[1 - v^2/c^2]

y = y'

z = z'

2. Relevant equations

show that

( 1 - [tex]\frac{u^{2}}{c^{2}}[/tex])(1+[tex]\frac{vux'^{2}}{c^{2}}[/tex]) = ( 1 - [tex]\frac{v^{2}}{c^{2}}[/tex])(1-[tex]\frac{u'^{2}}{c^{2}}[/tex])

3. The attempt at a solution

ok, I have spent many hours on this crappy thing. We have no book in class so.....

I derived the lorentz transformation for ux, uy, and uz... as well as u'x', u'y', u'z'.... then i computed the velocities in each fram using u = sqrt[ ux^2 + uy^2 + uz^2] and the same for u'. Nevertheless I end up in some mess of algebraic letters that get me nowhere close to the answer. I just need some sort of hit as to how to approach this problem.

thansk for any hints.

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# Homework Help: Lorentz's identity, relative speed

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