Solving a linear nonnegative inequality

Proved

WorkbookSource.problem_7992

by wamlart · Sep 12, 2026 · Mathlib 0df444a (Lean v4.33.1)

lean-workbooksource-checked

We also have $2x+1\geq 0$ $x\geq -\frac12$

Source: InternLM Lean-Workbook, record lean_workbook_7992 (Apache-2.0). The complete source proposition and explicit variable declarations are preserved.

Preamble

import Mathlib
open Real Nat

Formal statement

theorem WorkbookSource.problem_7992 (x:ℝ) : 2*x+1 >= 0 ↔ x >= -1/2  :=  by sorry

Source

https://huggingface.co/datasets/internlm/Lean-Workbook/blob/main/lean_workbook.json, record lean_workbook_7992; Apache-2.0

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