Generalized dihedral groups are ambivalent

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This article gives the statement, and possibly proof, of a particular group or type of group (namely, Generalized dihedral group (?)) satisfying a particular group property (namely, Ambivalent group (?)).

Statement

Let H be any abelian group and G be the generalized dihedral group corresponding to H. Then, G is an ambivalent group: every element of G is conjugate to its inverse. In particular, if G is finite, all characters of G are real-valued.

Related facts

Related facts about generalized dihedral groups

Related facts about similar groups

Proof

Proof outline

Any element in the abelian normal subgroup is conjugate to its inverse via the conjugating element. An element outside the abelian normal subgroup is an involution -- it has order two, so it is conjugate to its inverse for obvious reasons.