1 ⟨ x ⟩ ≤ ⟨ 1 x ⟩ {\displaystyle {\frac {1}{\left\langle x\right\rangle }}\leq \left\langle {\frac {1}{x}}\right\rangle }
⟨ x ⟩ ⟨ 1 x ⟩ ≥ 1 {\displaystyle \left\langle x\right\rangle \left\langle {\frac {1}{x}}\right\rangle \geq 1}