Question 1035704
{{{(x^2+1)/(1-x^2) = 221/220}}}  ==> {{{220x^2 + 220 = 221 - 220x^2}}}

==> {{{441x^2 = 1}}}  ==> {{{x^2 = 1/441}}}  ==> {{{x = 1/21}}} or {{{x = -1/21}}}.