I seem to remember this Algebra identity being covered in one of my classes years ago, but it has cropped back up in studying the relativistic doppler effect for light.(adsbygoogle = window.adsbygoogle || []).push({});

Can anyone please show me the intermediate steps to show that:

(1+x)/(sqrt(1-x^2) = sqrt((1+x)/(1-x))

or similarly

(sqrt(1-x^2)/(1+x) = sqrt((1-x)/(1+x))

I can solve problems well enough by factoring gamma out of these equations but it is bugging me that all the texts I can find keep taking this for granted and I can't see why.

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# B Algebra Identity I can't figure out

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