2 1 2*x ------ - --------- 2 2 x - 4 / 2 \ \x - 4/
1/(-4.0 + x^2) - 2.0*x^2/(-4.0 + x^2)^2
2 / 2\ 2 / 2\ \-4 + x / - 2*x *\-4 + x / --------------------------- 3 / 2\ \-4 + x /
2 -4 - x ---------- 2 / 2\ \-4 + x /
/ 2\ -\4 + x / -------------- 4 2 16 + x - 8*x
/ 2\ -\4 + x / ------------------ 2 2 (-2 + x) *(2 + x)