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