Metamath Proof Explorer


Theorem hmeocld

Description: Homeomorphisms preserve closedness. (Contributed by Jeff Madsen, 2-Sep-2009) (Proof shortened by Mario Carneiro, 25-Aug-2015)

Ref Expression
Hypothesis hmeoopn.1 𝑋 = 𝐽
Assertion hmeocld ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( 𝐴 ∈ ( Clsd ‘ 𝐽 ) ↔ ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) ) )

Proof

Step Hyp Ref Expression
1 hmeoopn.1 𝑋 = 𝐽
2 hmeocnvcn ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) → 𝐹 ∈ ( 𝐾 Cn 𝐽 ) )
3 2 adantr ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → 𝐹 ∈ ( 𝐾 Cn 𝐽 ) )
4 imacnvcnv ( 𝐹𝐴 ) = ( 𝐹𝐴 )
5 cnclima ( ( 𝐹 ∈ ( 𝐾 Cn 𝐽 ) ∧ 𝐴 ∈ ( Clsd ‘ 𝐽 ) ) → ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) )
6 4 5 eqeltrrid ( ( 𝐹 ∈ ( 𝐾 Cn 𝐽 ) ∧ 𝐴 ∈ ( Clsd ‘ 𝐽 ) ) → ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) )
7 6 ex ( 𝐹 ∈ ( 𝐾 Cn 𝐽 ) → ( 𝐴 ∈ ( Clsd ‘ 𝐽 ) → ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) ) )
8 3 7 syl ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( 𝐴 ∈ ( Clsd ‘ 𝐽 ) → ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) ) )
9 hmeocn ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) → 𝐹 ∈ ( 𝐽 Cn 𝐾 ) )
10 9 adantr ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → 𝐹 ∈ ( 𝐽 Cn 𝐾 ) )
11 cnclima ( ( 𝐹 ∈ ( 𝐽 Cn 𝐾 ) ∧ ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) ) → ( 𝐹 “ ( 𝐹𝐴 ) ) ∈ ( Clsd ‘ 𝐽 ) )
12 11 ex ( 𝐹 ∈ ( 𝐽 Cn 𝐾 ) → ( ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) → ( 𝐹 “ ( 𝐹𝐴 ) ) ∈ ( Clsd ‘ 𝐽 ) ) )
13 10 12 syl ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) → ( 𝐹 “ ( 𝐹𝐴 ) ) ∈ ( Clsd ‘ 𝐽 ) ) )
14 eqid 𝐾 = 𝐾
15 1 14 hmeof1o ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) → 𝐹 : 𝑋1-1-onto 𝐾 )
16 f1of1 ( 𝐹 : 𝑋1-1-onto 𝐾𝐹 : 𝑋1-1 𝐾 )
17 15 16 syl ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) → 𝐹 : 𝑋1-1 𝐾 )
18 f1imacnv ( ( 𝐹 : 𝑋1-1 𝐾𝐴𝑋 ) → ( 𝐹 “ ( 𝐹𝐴 ) ) = 𝐴 )
19 17 18 sylan ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( 𝐹 “ ( 𝐹𝐴 ) ) = 𝐴 )
20 19 eleq1d ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( ( 𝐹 “ ( 𝐹𝐴 ) ) ∈ ( Clsd ‘ 𝐽 ) ↔ 𝐴 ∈ ( Clsd ‘ 𝐽 ) ) )
21 13 20 sylibd ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) → 𝐴 ∈ ( Clsd ‘ 𝐽 ) ) )
22 8 21 impbid ( ( 𝐹 ∈ ( 𝐽 Homeo 𝐾 ) ∧ 𝐴𝑋 ) → ( 𝐴 ∈ ( Clsd ‘ 𝐽 ) ↔ ( 𝐹𝐴 ) ∈ ( Clsd ‘ 𝐾 ) ) )