Paper 1, Section II, F
Part II, 2010
(i) Let be a normal subgroup of the finite group . Without giving detailed proofs, define the process of lifting characters from to . State also the orthogonality relations for .
(ii) Let be the following two permutations in ,
and let , a subgroup of . Prove that is a group of order 12 and list the conjugacy classes of . By identifying a normal subgroup of of index 4 and lifting irreducible characters, calculate all the linear characters of . Calculate the complete character table of . By considering 6 th roots of unity, find explicit matrix representations affording the non-linear characters of .