A shifted squared pairwise reciprocal lower bound at fixed sum three
ProvedWorkbookSource.base_37690lean-workbooksource-checked
If x,y,z>0 and x+y+z=3 prove that
Source: InternLM Lean-Workbook, record lean_workbook_37690 (Apache-2.0). Complete source proposition preserved; proof developed independently.
Preamble
import Mathlib open Real Nat
Formal statement
theorem WorkbookSource.base_37690 (x y z : ℝ) (hx : 0 < x) (hy : 0 < y) (hz : 0 < z) (hx1 : x + y + z = 3) : 1 / (4 + (x + y) ^ 2) + 1 / (4 + (y + z) ^ 2) + 1 / (4 + (z + x) ^ 2) ≥ 3 / 8 := by sorry
Source