-- Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/NonUnital.lean
lemma cfcₙHom_of_cfcHom_map_quasispectrum {a : A} (ha : p a) :
    ∀ f : C(σₙ R a, R)₀, σₙ R (cfcₙHom_of_cfcHom R ha f) = range f

Proof state:
case h
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : R
⊢ x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0} ↔
    x ∈ range ⇑f

Tactic:
constructor

Result:
case h.mp
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : R
⊢ x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0} →
    x ∈ range ⇑f

case h.mpr
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : R
⊢ x ∈ range ⇑f →
    x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0}

Proof state:
case h.mpr.intro.inr.h
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x = 0
⊢ f x = 0

Tactic:
rw [show x = 0 from Subtype.val_injective hx, map_zero]

Result:
no goals

Proof state:
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
⊢ σₙ R ((cfcₙHom_of_cfcHom R ha) f) = range ⇑f

Tactic:
simp only [cfcₙHom_of_cfcHom]

Result:
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
⊢ σₙ R
      (((↑(cfcHom ha)).comp
          ((↑(compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ })).comp toContinuousMapHom))
        f) =
    range ⇑f

Proof state:
case h.mpr.intro.inr.h
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x ∈ {0}
⊢ f x ∈ {0}

Tactic:
simp only [Set.mem_singleton_iff] at hx ⊢

Result:
case h.mpr.intro.inr.h
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x = 0
⊢ f x = 0

Proof state:
case h.mpr.intro.inr
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x ∈ {0}
⊢ f x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0}

Tactic:
apply Or.inr

Result:
case h.mpr.intro.inr.h
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x ∈ {0}
⊢ f x ∈ {0}

Proof state:
case h.mpr.intro
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x ∈ spectrum R a ∪ {0}
⊢ f x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0}

Tactic:
obtain (hx | hx) := hx

Result:
case h.mpr.intro.inl
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x ∈ spectrum R a
⊢ f x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0}

case h.mpr.intro.inr
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
x : ↑(σₙ R a)
hx : ↑x ∈ {0}
⊢ f x ∈ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0}

Proof state:
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
⊢ spectrum R
        ((cfcHom ha)
          ((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f))) ∪
      {0} =
    range ⇑f

Tactic:
rw [cfcHom_map_spectrum ha]

Result:
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : Semifield R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : TopologicalSpace A
inst✝¹ : Algebra R A
inst✝ : ContinuousFunctionalCalculus R p
a : A
ha : p a
f : C(↑(σₙ R a), R)₀
⊢ range ⇑((compStarAlgHom' R R { toFun := Set.inclusion ⋯, continuous_toFun := ⋯ }) (toContinuousMapHom f)) ∪ {0} =
    range ⇑f