α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
u : Set ↑s
hu : MeasurableSet u
⊢ MeasurableSet (restrict s f '' u)
α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
⊢ ∀ ⦃s_1 : Set ↑s⦄, MeasurableSet s_1 → MeasurableSet (restrict s f '' s_1)
intro u hu
α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
u : Set ↑s
hu : MeasurableSet u
A : MeasurableSet (Subtype.val '' u)
⊢ MeasurableSet (restrict s f '' u)
α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
u : Set ↑s
hu : MeasurableSet u
⊢ MeasurableSet (restrict s f '' u)
have A : MeasurableSet (((↑) : s → γ) '' u) :=
  (MeasurableEmbedding.subtype_coe hs).measurableSet_image.2 hu
α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
u : Set ↑s
hu : MeasurableSet u
A : MeasurableSet (Subtype.val '' u)
B : MeasurableSet (f '' (Subtype.val '' u))
⊢ MeasurableSet (restrict s f '' u)
α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
u : Set ↑s
hu : MeasurableSet u
A : MeasurableSet (Subtype.val '' u)
⊢ MeasurableSet (restrict s f '' u)
have B : MeasurableSet (f '' (((↑) : s → γ) '' u)) :=
  A.image_of_continuousOn_injOn (f_cont.mono (Subtype.coe_image_subset s u))
    (f_inj.mono (Subtype.coe_image_subset s u))
no goals
α : Type ?u.323269
inst✝⁵ : TopologicalSpace α
ι : Type ?u.323275
γ : Type u_1
tγ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : MeasurableSpace γ
hγb : BorelSpace γ
β : Type u_2
tβ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : BorelSpace β
s : Set γ
f : γ → β
hs : MeasurableSet s
f_cont : ContinuousOn f s
f_inj : InjOn f s
u : Set ↑s
hu : MeasurableSet u
A : MeasurableSet (Subtype.val '' u)
B : MeasurableSet (f '' (Subtype.val '' u))
⊢ MeasurableSet (restrict s f '' u)
rwa [← image_comp] at B