A refined squared reciprocal sum inequality
ProvedWorkbookSource.base_18254lean-workbooksource-checked
Let a,b,c>0.Prove:
Source: InternLM Lean-Workbook, record lean_workbook_18254 (Apache-2.0). Complete source proposition preserved; proof developed independently.
Preamble
import Mathlib open Real Nat
Formal statement
theorem WorkbookSource.base_18254 (a b c : ℝ) (ha : a > 0) (hb : b > 0) (hc : c > 0) : (1 / a ^ 2 + 1 / b ^ 2 + 1 / c ^ 2 + 1 / (a + b + c) ^ 2) ≥ (7 / 25) * (1 / a + 1 / b + 1 / c + 1 / (a + b + c)) ^ 2 := by sorry
Source