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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