Embed the order-eight dihedral group as in the symmetric group , and let be its two-dimensional complex representation obtained from its square action. Let be the three-dimensional complex representation from the rotational symmetry group of a cube. In the class order , the induced character is : only the identity and the square's half-turn have nonzero character values. This equals the character of , since . Characters distinguish finite-dimensional complex semisimple representations, giving the displayed isomorphism. Its trivial character multiplicity is .
In the order of conjugacy classes used in part (c), the elements of have the following types:By part (d), only and have nonzero character values. Formula (b), or equivalently the element-sum version proved there, therefore giveswith zero on the other three conjugacy classes. Here the centralizer order is . Thus .
Let denote the sign representation and take the explicit two-dimensional -moduleIts character is . The character of a tensor product of group representations is the pointwise product of their characters, because . ConsequentlyBy Maschke's theorem both complex representations are semisimple representations, and characters distinguish finite-dimensional complex semisimple representations. ThereforeThis is the induction of the planar square representation to the symmetric group on four letters.
The dimension of the fixed-point subspace of a group action is the multiplicity of the trivial representation. Its character inner product here isHence . Equivalently, Frobenius reciprocity identifies this multiplicity with .