AlgebraicUnitQ

AlgebraicUnitQ[a] yields True if a is an algebraic unit, and yields False otherwise.

Examples

Test if a number is an algebraic unit:

AlgebraicUnitQ[1 + Sqrt[2]]
(* True *)

An integer other than ±1 is not an algebraic unit:

AlgebraicUnitQ[2]
(* False *)

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