I found-out that complex cube-root can have 3 variants (see http://en.wikipedia.org/wiki/Cube_root)
But if I try in SageMath to do
(-1)^(1/3)
SageMath return (-1)^(1/3). When I try
(-1)^(1/3).n()
SageMath gives me numerical approximation of the one root (not real)...
How I can get all variants of complex cube-root without numerical approximation?
Thanks! P.S. Sorry for poor English...