This question is ambiguous. There are two possibilities:
(1) 1/(x-1)<1/(x+1)⇒(multiplying through by x2-1) x+1<x-1⇒1<-1 which is FALSE, if x2-1>0, that is, (x-1)(x+1)>0⇒ x-1>0 and x+1>0⇒x>1; or x-1<0 and x+1<0⇒x<-1. If x2-1<0 then -1<x<1, then the inequality is TRUE.
(2) (1/x)-1<(1/x)+1⇒-1<1 which is TRUE for all x.
The most likely answer is (1): -1<x<1, that is, x can be any value between -1 and 1 (exclusively). Example: x=½: -2<⅔; x=-½: -⅔<2.