lean_workbook_plus_55211
ProvedSuppose are the sides of a triangle. Prove or disprove .
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_55211 {a b c : ℝ} (hx: a > 0 ∧ b > 0 ∧ c > 0) (hab : a + b > c) (hbc : b + c > a) (hca : a + c > b) : (2 * b - c) * a ^ 2 + (2 * c - a) * b ^ 2 + (2 * a - b) * c ^ 2 >= 3 * a * b * c := by sorrySource