Question 231420
{{{ ((x+1)/(x-1))+((1-x)/(x+1)) }}}
={{{((x+1)^2+(1-x)(x-1))/((x-1)(x+1))}}}
={{{(x^2+2x+1-x^2+2x-1)/(x^2-1)}}}
={{{4x/(x^2-1)}}}
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Ed