NumberFieldRootsOfUnity

NumberFieldRootsOfUnity[a] gives the roots of unity for the field ℚ[a] generated by the algebraic number a.

Examples

NumberFieldRootsOfUnity[Sqrt[5]]
(* {2, -1} *)

NumberFieldRootsOfUnity[Exp[2 Pi I/6]]
(* {6, E^(I Pi/3)} *)

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