lean_workbook_plus_30303
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.
So all the solutions are given by
Why this node was retired
The posted statement is
theorem lean_workbook_plus_30303 : {(x, y) : ℚ × ℚ | x^2 + 2 * y^2 = 1 ∧ x ≠ 0 ∧ y ≠ 0} = {(x, y) : ℚ × ℚ | ∃ m : ℚ, x = -(m^2 + 2) / (m^2 - 10 * m - 2) ∧ y = (10 - 2 * m) / (m^2 - 10 * m - 2)} ∪ {(x, y) : ℚ × ℚ | x = 1 ∧ y = 0} ∪ {(x, y) : ℚ × ℚ | x = -1 ∧ y = 0} ∪ {(x, y) : ℚ × ℚ | x = 0 ∧ y = 1} ∪ {(x, y) : ℚ × ℚ | x = 0 ∧ y = -1} := by sorry
The formal statement changes or incorrectly supplies part of the source problem; the accepted note identifies a concrete witness or definitional mechanism.
The recorded counterexample refutes the statement as encoded. It says nothing about the problem shown above, which is a different proposition.
Proposed corrected statement
If the intended conic is x²+2y²=1, classify all rational points as ((1−2t²)/(1+2t²),2t/(1+2t²)) for t∈ℚ, together with (−1,0); add x≠0,y≠0 only by filtering this entire set. The supplied excerpt may concern a different conic, so its parameterization cannot be faithfully repaired without that original equation.
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_30303 : {(x, y) : ℚ × ℚ | x^2 + 2 * y^2 = 1 ∧ x ≠ 0 ∧ y ≠ 0} = {(x, y) : ℚ × ℚ | ∃ m : ℚ, x = -(m^2 + 2) / (m^2 - 10 * m - 2) ∧ y = (10 - 2 * m) / (m^2 - 10 * m - 2)} ∪ {(x, y) : ℚ × ℚ | x = 1 ∧ y = 0} ∪ {(x, y) : ℚ × ℚ | x = -1 ∧ y = 0} ∪ {(x, y) : ℚ × ℚ | x = 0 ∧ y = 1} ∪ {(x, y) : ℚ × ℚ | x = 0 ∧ y = -1} := by sorry