∀ (l : Type u_4) (R : Type u₂) [inst : DecidableEq l] [inst_1 : CommRing R] [inst_2 : Fintype l]
  [inst_3 : Invertible 2], LieAlgebra.Orthogonal.PD l R * ⅟2 • (LieAlgebra.Orthogonal.PD l R).transpose = 1