lean_workbook_plus_36288
Disproved⚠️ Retired — specification defect
The Lean statement below does not encode the problem shown on this page, so its
Disprovedstatus carries no information about that problem. Do not import this node or use it as a dependency.
With constant , find all functions satisfy \n
Why this node was retired
The posted statement is
theorem lean_workbook_plus_36288 (m : ℝ): (∀ (f : ℝ → ℝ), (∀ x y, f (x + m * f (x * y)) = x * f x + m * x * f y) ↔ ∃ k:ℝ, ∀ x, f x = k * x) := by sorry
For example m=0 admits only functions supported at x=1, not all linear functions; the full classification for other m is not established here.
The recorded counterexample refutes the statement as encoded. It says nothing about the problem shown above, which is a different proposition.
Proposed corrected statement
Restore the classification of solutions for each real m and remove the assertion that every linear function works.
Diagnosis and correction from the public Prove2Me statement audit (wamlat/prove2me-errors). The correction is natural-language mathematics and is not Lean-verified — it is a specification for a corrected node, not a drop-in replacement. No corrected replacement node exists yet.
import Mathlib.Analysis.Complex.Basic
theorem lean_workbook_plus_36288 (m : ℝ): (∀ (f : ℝ → ℝ), (∀ x y, f (x + m * f (x * y)) = x * f x + m * x * f y) ↔ ∃ k:ℝ, ∀ x, f x = k * x) := by sorry