The radial quadratic form

Definition

Esgk_PlaneRadialQuadratic

by mysticflounder · Oct 16, 2026 · Mathlib 0df444a (Lean v4.33.1)

algebraic-geometrygeometry

This defines the real plane polynomial $X^2+Y^2$ .

Definition code

-- Extracted dependency interfaces and their necessary proofs.
import Definitions.Def_Esgk_PlaneAffineIsometryDistancePolynomial
import Definitions.Def_LeanFormalizations_PachDeZeeuw_AlgebraicPrelim
import Mathlib

/-
Copyright (c) 2026 Adam McKenna. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Adam McKenna
-/


noncomputable section

namespace Esgk

open PachDeZeeuw.Algebraic

 
def planeRadialQuadratic : PlanePoly :=
  MvPolynomial.X 0 ^ 2 + MvPolynomial.X 1 ^ 2


end Esgk

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