-- Mathlib/Geometry/Manifold/IsManifold/Basic.lean
theorem contDiffGroupoid_zero_eq : contDiffGroupoid 0 I = continuousGroupoid H

Proof state:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ { property := fun f s => ContDiffOn 𝕜 0 (↑I ∘ f ∘ ↑I.symm) (↑I.symm ⁻¹' s ∩ range ↑I), comp := ⋯, id_mem := ⋯,
          locality := ⋯, congr := ⋯ }.property
      (↑u) u.source ∧
    { property := fun f s => ContDiffOn 𝕜 0 (↑I ∘ f ∘ ↑I.symm) (↑I.symm ⁻¹' s ∩ range ↑I), comp := ⋯, id_mem := ⋯,
          locality := ⋯, congr := ⋯ }.property
      (↑u.symm) u.target

Tactic:
simp only [contDiffOn_zero]

Result:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ ContinuousOn (↑I ∘ ↑u ∘ ↑I.symm) (↑I.symm ⁻¹' u.source ∩ range ↑I) ∧
    ContinuousOn (↑I ∘ ↑u.symm ∘ ↑I.symm) (↑I.symm ⁻¹' u.target ∩ range ↑I)

Proof state:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
⊢ ⊤ ≤ contDiffGroupoid 0 I

Tactic:
intro u _

Result:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ u ∈ (contDiffGroupoid 0 I).members

Proof state:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ u ∈ contDiffGroupoid 0 I

Tactic:
rw [contDiffGroupoid, mem_groupoid_of_pregroupoid, contDiffPregroupoid]

Result:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ { property := fun f s => ContDiffOn 𝕜 0 (↑I ∘ f ∘ ↑I.symm) (↑I.symm ⁻¹' s ∩ range ↑I), comp := ⋯, id_mem := ⋯,
          locality := ⋯, congr := ⋯ }.property
      (↑u) u.source ∧
    { property := fun f s => ContDiffOn 𝕜 0 (↑I ∘ f ∘ ↑I.symm) (↑I.symm ⁻¹' s ∩ range ↑I), comp := ⋯, id_mem := ⋯,
          locality := ⋯, congr := ⋯ }.property
      (↑u.symm) u.target

Proof state:
case left
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ MapsTo (↑I.symm) (↑I.symm ⁻¹' u.source ∩ range ↑I) u.source

Tactic:
exact (mapsTo_preimage _ _).mono_left inter_subset_left

Result:
no goals

Proof state:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ ContinuousOn (↑I ∘ ↑u ∘ ↑I.symm) (↑I.symm ⁻¹' u.source ∩ range ↑I) ∧
    ContinuousOn (↑I ∘ ↑u.symm ∘ ↑I.symm) (↑I.symm ⁻¹' u.target ∩ range ↑I)

Tactic:
constructor

Result:
case left
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ ContinuousOn (↑I ∘ ↑u ∘ ↑I.symm) (↑I.symm ⁻¹' u.source ∩ range ↑I)

case right
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ ContinuousOn (↑I ∘ ↑u.symm ∘ ↑I.symm) (↑I.symm ⁻¹' u.target ∩ range ↑I)

Proof state:
case right
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ ContinuousOn (↑I ∘ ↑u.symm ∘ ↑I.symm) (↑I.symm ⁻¹' u.target ∩ range ↑I)

Tactic:
refine I.continuous.comp_continuousOn (u.symm.continuousOn.comp I.continuousOn_symm ?_)

Result:
case right
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ MapsTo (↑I.symm) (↑I.symm ⁻¹' u.target ∩ range ↑I) u.symm.source

Proof state:
case left
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ ContinuousOn (↑I ∘ ↑u ∘ ↑I.symm) (↑I.symm ⁻¹' u.source ∩ range ↑I)

Tactic:
refine I.continuous.comp_continuousOn (u.continuousOn.comp I.continuousOn_symm ?_)

Result:
case left
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ MapsTo (↑I.symm) (↑I.symm ⁻¹' u.source ∩ range ↑I) u.source

Proof state:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ u ∈ (contDiffGroupoid 0 I).members

Tactic:
change u ∈ contDiffGroupoid 0 I

Result:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ u ∈ contDiffGroupoid 0 I

Proof state:
case right
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
u : PartialHomeomorph H H
a✝ : u ∈ ⊤.members
⊢ MapsTo (↑I.symm) (↑I.symm ⁻¹' u.target ∩ range ↑I) u.symm.source

Tactic:
exact (mapsTo_preimage _ _).mono_left inter_subset_left

Result:
no goals

Proof state:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
⊢ contDiffGroupoid 0 I = continuousGroupoid H

Tactic:
apply le_antisymm le_top

Result:
𝕜 : Type u_1
inst✝³ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
H : Type u_3
inst✝ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
⊢ ⊤ ≤ contDiffGroupoid 0 I