3 -1 + 3*x --------- 3
/ 2/3\ / 2/3 6 ___\ / 2/3 6 ___\ | 3 | | 3 I*\/ 3 | | 3 I*\/ 3 | |x - ----|*|x + ---- + -------|*|x + ---- - -------| \ 3 / \ 6 2 / \ 6 2 /