theorem
proved
term proof
goldenDivision_ratio
show as:
view Lean formalization →
formal statement (Lean)
47theorem goldenDivision_ratio : (1 - goldenDivision) / goldenDivision = phi - 1 := by
proof body
Term-mode proof.
48 unfold goldenDivision
49 have hphi_ne := phi_ne_zero
50 have hinv_ne : phi⁻¹ ≠ 0 := inv_ne_zero hphi_ne
51 rw [div_eq_iff hinv_ne]
52 have : phi * phi⁻¹ = 1 := mul_inv_cancel₀ hphi_ne
53 nlinarith [this]
54