2/ x^2 - 9xy^2 - 3/3x + 12y
If you mean
2/(x^2-9xy^2) - 3/(3x+12y)
then that's
2 / x(x-9y^2) - 1/(x+4y)
(-x^2+9xy^2+2x+8y)/(x^3-9x^2y^2+4x^2y-36xy^3)
I suspect a typo
2/(x^2-9xy^2) - 3/(3x+12y)
then that's
2 / x(x-9y^2) - 1/(x+4y)
(-x^2+9xy^2+2x+8y)/(x^3-9x^2y^2+4x^2y-36xy^3)
I suspect a typo