2 1 + 2*x ----------- 2 / 2\ x *\1 + x /
(1 + 2*x^2)/((x^2*(1 + x^2)))
x^(-2) + 1/(1 + x^2)
1 1 -- + ------ 2 2 x 1 + x
2 1 + 2*x -------- 2 4 x + x
(1 + 2*x^2)/(x^2 + x^4)
(1.0 + 2.0*x^2)/(x^2*(1.0 + x^2))