A reciprocal-total product inequality with a pair-product correction
ProvedWorkbookSource.base_9999lean-workbooksource-checked
,prove
Source: InternLM Lean-Workbook, record lean_workbook_9999 (Apache-2.0). Complete source proposition preserved; proof developed independently.
Preamble
import Mathlib open Real Nat
Formal statement
theorem WorkbookSource.base_9999 (a b c d : ℝ) (ha : 0 < a) (hb : 0 < b) (hc : 0 < c) (hd : 0 < d) : (a + b + c + d) * (1 / a + 1 / b + 1 / c + 1 / d) + 8 ≥ 9 * (a + b + c + d) ^ 2 / (a * b + b * c + c * d + a * d + a * c + b * d) := by sorry
Source