(i) Let G be a finite group. Show that
(1) If χ is an irreducible character of G then so is its conjugate χˉ.
(2) The product of any two characters of G is again a character of G.
(3) If χ and ψ are irreducible characters of G then
⟨χψ,1G⟩={1,0, if χ=ψˉ, if χ=ψˉ.
(ii) If χ is a character of the finite group G, define χS and χA. For g∈G prove that
χS(g)=21(χ2(g)+χ(g2)) and χA(g)=21(χ2(g)−χ(g2))
(iii) A certain group of order 24 has precisely seven conjugacy classes with representatives g1,…,g7; further, G has a character χ with values as follows:
gi∣CG(gi)∣χg1242g224−2g340g46−ω2g56−ωg66ωg76ω2
where ω=e2πi/3.
It is given that g12,g22,g32,g42,g52,g62,g72 are conjugate to g1,g1,g2,g5,g4,g4,g5 respectively.
Determine χS and χA, and show that both are irreducible.