We have `underset(xto1)lim((2)/(1-x^(2))+(1)/(x+1))" "(oo-oo"from")` `=underset(xto1)lim((2)/(1-x^(2))-(1)/(1-x))` When x=1, the expression `(2)/(1-x^(2))-(1)/(1-x)` assumes the form `oo-oo.` So, we need some simplifieation to express it in the form 0/0. Then, `underset(xto1)lim((2)/(1-x^(2))-(1)/(1-x))=underset(xto1)lim(2-(1+x))/(1-x^(2))=underset(xto1)lim(1-x)/(1-x^(2))=underset(xto1)lim(1)/(1+x)=1/2`