theorem
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phi_inverse_formula
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IndisputableMonolith.Unification.ConstantsPredictionsProved on GitHub at line 169.
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166/-! ## Section: Additional Phi Bounds -/
167
168/-- **CALCULATED**: φ⁻¹ = φ - 1 (inverse formula). -/
169theorem phi_inverse_formula : 1 / phi = phi - 1 := by
170 have h1 : phi > 0 := phi_pos
171 have h2 : phi^2 = phi + 1 := phi_sq_eq
172 field_simp
173 nlinarith
174
175/-- **CALCULATED**: φ + 1/φ = √5. -/
176theorem phi_plus_inverse_eq_sqrt5 : phi + 1/phi = Real.sqrt 5 := by
177 rw [phi_inverse_formula]
178 have h1 : phi^2 = phi + 1 := phi_sq_eq
179 have h2 : (2 * phi - 1)^2 = 5 := by
180 nlinarith
181 have h3 : 2 * phi - 1 > 0 := by
182 have h4 : phi > 1.5 := phi_gt_onePointFive
183 linarith
184 have h4 : Real.sqrt ((2 * phi - 1)^2) = Real.sqrt 5 := by
185 rw [h2]
186 have h5 : Real.sqrt ((2 * phi - 1)^2) = 2 * phi - 1 := by
187 apply Real.sqrt_sq
188 linarith
189 nlinarith
190
191/-- **CALCULATED**: φ² > 2.5. -/
192theorem phi_sq_gt_2_5 : phi^2 > (2.5 : ℝ) := by
193 have h1 : phi^2 = phi + 1 := phi_sq_eq
194 rw [h1]
195 have h2 : phi > 1.5 := phi_gt_onePointFive
196 nlinarith
197
198/-- **CALCULATED**: φ² < 2.7. -/
199theorem phi_sq_lt_2_7 : phi^2 < (2.7 : ℝ) := by