try long division
0.25f^2 + 0.5f + 1
(0.5f - 1) / (0.125f^3 - 1)
0.125f^3 - 0.25f^2
------------------------
0 + 0.25f^2 - 1
0.25f^2 - 0.5f
---------------------
0 + 0.5f - 1
0.5f - 1
----------------
0 + 0
solution: last one
(0.5f - 1)(0.25f^2 + 0.5f + 1)
