A nonnegative sixth degree polynomial

Proved

WorkbookSource.problem_39879

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

lean-workbooksource-checked

Let $x\geq 0$ ,prove that: $3.x^6+2x+2x^2+x^3-x^4-2x^5\geq 0$

Source: InternLM Lean-Workbook, record lean_workbook_39879 (Apache-2.0). The complete source proposition and its explicit variable declarations are preserved.

Preamble

import Mathlib
open Real

Formal statement

theorem WorkbookSource.problem_39879 (x : ℝ) (hx: x >= 0) : 3 * x^6 + 2 * x + 2 * x^2 + x^3 - x^4 - 2 * x^5 >= 0  :=  by sorry

Source

https://huggingface.co/datasets/internlm/Lean-Workbook/blob/main/lean_workbook.json, record lean_workbook_39879; Apache-2.0

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