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