3 2 126*x + 3*x + 3*x + 1
126*x^3 + 3*x^2 + 3*x + 1
/ ___\ / ___\ | 1 5*I*\/ 3 | | 1 5*I*\/ 3 | 1*(x + 1/6)*|x + - -- + ---------|*|x + - -- - ---------| \ 14 42 / \ 14 42 /
((1*(x + 1/6))*(x - (1/14 + 5*i*sqrt(3)/42)))*(x - (1/14 - 5*i*sqrt(3)/42))
/ 2\ (1 + 6*x)*\1 - 3*x + 21*x /
(1 + 6*x)*(1 - 3*x + 21*x^2)