Nuprl Lemma : homeo-image-inverse
∀[X,Y:Type]. ∀[dX:metric(X)]. ∀[dY:metric(Y)]. ∀[h:homeomorphic(X;dX;Y;dY)]. ∀[A:Type].
  homeo-image(homeo-image(A;Y;dY;h);X;dX;homeo-inv(h)) ≡ A supposing metric-subspace(X;dX;A)
Proof
Definitions occuring in Statement : 
homeo-image: homeo-image(A;Y;dY;h)
, 
metric-subspace: metric-subspace(X;d;A)
, 
homeo-inv: homeo-inv(h)
, 
homeomorphic: homeomorphic(X;dX;Y;dY)
, 
metric: metric(X)
, 
ext-eq: A ≡ B
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
metric-subspace: metric-subspace(X;d;A)
, 
and: P ∧ Q
, 
uiff: uiff(P;Q)
, 
ext-eq: A ≡ B
, 
subtype_rel: A ⊆r B
, 
homeo-image: homeo-image(A;Y;dY;h)
, 
prop: ℙ
, 
exists: ∃x:A. B[x]
, 
homeomorphic: homeomorphic(X;dX;Y;dY)
, 
homeo-inv: homeo-inv(h)
, 
pi1: fst(t)
, 
sq_exists: ∃x:A [B[x]]
, 
mfun: FUN(X ⟶ Y)
, 
is-mfun: f:FUN(X;Y)
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
so_apply: x[s]
, 
guard: {T}
, 
label: ...$L... t
, 
meq: x ≡ y
, 
req: x = y
, 
sq_stable: SqStable(P)
, 
squash: ↓T
, 
rev_uimplies: rev_uimplies(P;Q)
Latex:
\mforall{}[X,Y:Type].  \mforall{}[dX:metric(X)].  \mforall{}[dY:metric(Y)].  \mforall{}[h:homeomorphic(X;dX;Y;dY)].  \mforall{}[A:Type].
    homeo-image(homeo-image(A;Y;dY;h);X;dX;homeo-inv(h))  \mequiv{}  A  supposing  metric-subspace(X;dX;A)
Date html generated:
2020_05_20-AM-11_51_10
Last ObjectModification:
2019_11_20-AM-10_57_17
Theory : reals
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