(T : F →L[ℂ] F) (b : HilbertBasis ℕ ℂ F) (k : ℕ) : (minmaxSet T k).Nonempty

-- Generated from ChapterSirkRitzMinMax.lean — theorem BookProof.RitzMinMax.minmaxSet_nonempty
import Mathlib
import Definitions.Def_ChapterSirkRitzMinMax
open BookProof.RitzMinMax









noncomputable section


open BookProof.HermiteGalerkin BookProof.ChapterSirkRitzSpectrum
open Filter Topology

variable {F : Type*} [NormedAddCommGroup F] [InnerProductSpace ℂ F] [CompleteSpace F]

theorem BookProof.RitzMinMax.minmaxSet_nonempty (T : F →L[ℂ] F) (b : HilbertBasis ℕ ℂ F) (k : ℕ) :
    (minmaxSet T k).Nonempty := by sorry