theorem dtc_bias_invariant_cobbDouglas {K L : ℝ} (_hK : 0 < K) (_hL : 0 < L) :
dtcEquilibriumBias 1 (K / L) = 1 := by
simp only [dtcEquilibriumBias]
rw [show (1 : ℝ) - 1 = 0 from by ring]
exact rpow_zero _Directed Technical Change Extension (Acemoglu 2002)