2 4 6 64*c *d - 4*n
(64*c^2)*d^4 - 4*n^6
-4.0*n^6 + 64.0*c^2*d^4
/ 6 2 4\ 4*\- n + 16*c *d /
4*(-n^6 + 16*c^2*d^4)
/ 3 2\ / 3 2\ 4*\n + 4*c*d /*\- n + 4*c*d /
4*(n^3 + 4*c*d^2)*(-n^3 + 4*c*d^2)