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by naaga » Sat Mar 07, 2009 4:47 am
If x doesn't equal to 1 and -1 , then (x+1/x-1) - ( x-1/x+1) = ?


folks, no options are available for this question. kindly explain

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by DanaJ » Sat Mar 07, 2009 8:10 am
Bring these two elements to common numerator:
(x+1/x-1) - ( x-1/x+1) = [(x + 1)^2 - (x - 1)^2]/(x^2 - 1) = 4x/(x^2 - 1).
I don't know if you can take it anywhere further without any other info...