3 3 z + I
z^3 + i^3
3 z - I
z^3 - i
/ ___\ / ___\ | I \/ 3 | | I \/ 3 | (x + I)*|x + - - + -----|*|x + - - - -----| \ 2 2 / \ 2 2 /
((x + i)*(x - i/2 + sqrt(3)/2))*(x - i/2 - sqrt(3)/2)