Galois Group of Cyclotomic Extensions Over Q Algebra Block Triangular Determinant Linear Algebra Conjugacy Classes in $\operatorname{SU}(2)$ Representation Theory Three by Three Lemma Algebra SO3 Rotation Theorem Group Theory Orthogonal Projection Linear Algebra Noetherian Characterisation by Finitely Generated Submodules Algebra Degree of a One-Step Construction Algebra Algebra Area