Lean-Workbook Plus 71177: Logarithmic inequality

Proved

WorkbookRestored.plus_71177

by wamlart · Sep 12, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

lean-workbookrestored-importssource-checked

There exists a real $x>0$ , $x\ne2$ , satisfying $\log_2x=x/2$ .

Source: Lean-Workbook row lean_workbook_plus_71177 (Apache-2.0). The unchanged proposition comes from the original record; its missing mathematical imports and namespaces are restored here.

Preamble

import Mathlib.Analysis.SpecialFunctions.Log.Base
open Real

Formal statement

theorem WorkbookRestored.plus_71177 : ∃ x : ℝ, 0 < x ∧ x ≠ 2 ∧ Real.logb 2 x = x / 2   :=  by sorry

Source

https://huggingface.co/datasets/internlm/Lean-Workbook/blob/main/lean_workbook.json, row lean_workbook_plus_71177; immutable original Prove2Me node d35e14e5-8370-475d-a651-f76c1b3db4a0

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