∀ {A : Type u_1} [inst : PartialOrder A] [inst_1 : Ring A] [inst_2 : StarRing A] [inst_3 : TopologicalSpace A]
  [inst_4 : StarOrderedRing A] [inst_5 : Algebra ℝ A] [inst_6 : ContinuousFunctionalCalculus ℝ A IsSelfAdjoint]
  [inst_7 : NonnegSpectrumClass ℝ A] {a : A} (x : ℝ),
  IsUnit a → autoParam (0 ≤ a) CFC.rpow_mul_rpow_neg._auto_1 → a ^ x * a ^ (-x) = 1