2 2*x + 4
2*x^2 + 4
/ ___\ / ___\ \x + I*\/ 2 /*\x - I*\/ 2 /
(x + i*sqrt(2))*(x - i*sqrt(2))
/ 2\ 2*\2 + x /
2*(2 + x^2)
4.0 + 2.0*x^2