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