fact: Definition leℚ_tight := λ"q₁" λ"q₂" λ"f" ℚle @ "q₁" @ "q₂" @ Id @ (Qq 2%nat @ (ℚsub @ "q₁" @ "q₂" @ ℚdiv) @ "f").
imports: QArith ClassicalRealizability.Qcabs ClassicalRealizability.Qcminmax ClassicalRealizability.Kbase