Rearranging equation - Relativistic doppler

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roberto85
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Homework Statement


The hydra cluster is 900 Mpc (3x10^9 light years) away. Calcium atoms emit a spectral line of wavelength 396.8 nm. This line is observed at 487.5 nm. The velocity of the cluster, v, is given by ([tex]\lambda[/tex] =c/f)

487.5 = 396.8 SQRT((1+v/c)/(1-v/c))

How do i find v please?


Homework Equations





The Attempt at a Solution

I need to rearrange and this example says take v/c to one side and solve but i don't know how. Well i have taken the numbers to one side, squared them and left with (1+v/c)/(1-v/c) on the other side, how do i find v? Thanks
 
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  1. Divide both sides by 396.8.
  2. Square both sides.
  3. Multiply both sides by (1 - v/c).
  4. Carry out the multiplication on the left side.
  5. Get all terms involving v on one side.
  6. Factor v out.
  7. Divide both sides by the coefficient of v.
That should pretty much do it