A quadratic-factor product bound above one
ProvedWorkbookSource.base_8123lean-workbooksource-checked
Let , Prove that :
Source: InternLM Lean-Workbook, record lean_workbook_8123 (Apache-2.0). Complete source proposition preserved; proof developed independently.
Preamble
import Mathlib open Real Nat
Formal statement
theorem WorkbookSource.base_8123 (a b c : ℝ) (ha : 1 ≤ a) (hb : 1 ≤ b) (hc : 1 ≤ c) : (2 * a ^ 2 + 1) * (2 * b ^ 2 + 1) * (2 * c ^ 2 + 1) ≥ 3 * (a + b + c) ^ 2 := by sorry
Source