2 4 36*x - 81*y
36*x^2 - 81*y^4
/ 2\ / 2\ | 3*y | | 3*y | 1*|x + ----|*|x - ----| \ 2 / \ 2 /
(1*(x + 3*y^2/2))*(x - 3*y^2/2)
36.0*x^2 - 81.0*y^4
/ 4 2\ 9*\- 9*y + 4*x /
9*(-9*y^4 + 4*x^2)
/ 2 \ / 2\ 9*\- 3*y + 2*x/*\2*x + 3*y /
9*(-3*y^2 + 2*x)*(2*x + 3*y^2)