lean_workbook_plus_18742

Proved

by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

Explain how to solve the inequality $x^2 - 16 \geq 0$ algebraically without factoring.

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_18742 (x : ℝ) : x^2 - 16 ≥ 0 ↔ x ≥ 4 ∨ x ≤ -4   :=  by sorry

Source