Metamath Proof Explorer


Theorem mrcun

Description: Idempotence of closure under a pair union. (Contributed by Stefan O'Rear, 31-Jan-2015)

Ref Expression
Hypothesis mrcfval.f 𝐹 = ( mrCls ‘ 𝐶 )
Assertion mrcun ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 ‘ ( 𝑈𝑉 ) ) = ( 𝐹 ‘ ( ( 𝐹𝑈 ) ∪ ( 𝐹𝑉 ) ) ) )

Proof

Step Hyp Ref Expression
1 mrcfval.f 𝐹 = ( mrCls ‘ 𝐶 )
2 simp1 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → 𝐶 ∈ ( Moore ‘ 𝑋 ) )
3 mre1cl ( 𝐶 ∈ ( Moore ‘ 𝑋 ) → 𝑋𝐶 )
4 elpw2g ( 𝑋𝐶 → ( 𝑈 ∈ 𝒫 𝑋𝑈𝑋 ) )
5 3 4 syl ( 𝐶 ∈ ( Moore ‘ 𝑋 ) → ( 𝑈 ∈ 𝒫 𝑋𝑈𝑋 ) )
6 5 biimpar ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋 ) → 𝑈 ∈ 𝒫 𝑋 )
7 6 3adant3 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → 𝑈 ∈ 𝒫 𝑋 )
8 elpw2g ( 𝑋𝐶 → ( 𝑉 ∈ 𝒫 𝑋𝑉𝑋 ) )
9 3 8 syl ( 𝐶 ∈ ( Moore ‘ 𝑋 ) → ( 𝑉 ∈ 𝒫 𝑋𝑉𝑋 ) )
10 9 biimpar ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑉𝑋 ) → 𝑉 ∈ 𝒫 𝑋 )
11 10 3adant2 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → 𝑉 ∈ 𝒫 𝑋 )
12 7 11 prssd ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → { 𝑈 , 𝑉 } ⊆ 𝒫 𝑋 )
13 1 mrcuni ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ { 𝑈 , 𝑉 } ⊆ 𝒫 𝑋 ) → ( 𝐹 { 𝑈 , 𝑉 } ) = ( 𝐹 ( 𝐹 “ { 𝑈 , 𝑉 } ) ) )
14 2 12 13 syl2anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 { 𝑈 , 𝑉 } ) = ( 𝐹 ( 𝐹 “ { 𝑈 , 𝑉 } ) ) )
15 uniprg ( ( 𝑈 ∈ 𝒫 𝑋𝑉 ∈ 𝒫 𝑋 ) → { 𝑈 , 𝑉 } = ( 𝑈𝑉 ) )
16 7 11 15 syl2anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → { 𝑈 , 𝑉 } = ( 𝑈𝑉 ) )
17 16 fveq2d ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 { 𝑈 , 𝑉 } ) = ( 𝐹 ‘ ( 𝑈𝑉 ) ) )
18 1 mrcf ( 𝐶 ∈ ( Moore ‘ 𝑋 ) → 𝐹 : 𝒫 𝑋𝐶 )
19 18 ffnd ( 𝐶 ∈ ( Moore ‘ 𝑋 ) → 𝐹 Fn 𝒫 𝑋 )
20 19 3ad2ant1 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → 𝐹 Fn 𝒫 𝑋 )
21 fnimapr ( ( 𝐹 Fn 𝒫 𝑋𝑈 ∈ 𝒫 𝑋𝑉 ∈ 𝒫 𝑋 ) → ( 𝐹 “ { 𝑈 , 𝑉 } ) = { ( 𝐹𝑈 ) , ( 𝐹𝑉 ) } )
22 20 7 11 21 syl3anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 “ { 𝑈 , 𝑉 } ) = { ( 𝐹𝑈 ) , ( 𝐹𝑉 ) } )
23 22 unieqd ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 “ { 𝑈 , 𝑉 } ) = { ( 𝐹𝑈 ) , ( 𝐹𝑉 ) } )
24 fvex ( 𝐹𝑈 ) ∈ V
25 fvex ( 𝐹𝑉 ) ∈ V
26 24 25 unipr { ( 𝐹𝑈 ) , ( 𝐹𝑉 ) } = ( ( 𝐹𝑈 ) ∪ ( 𝐹𝑉 ) )
27 23 26 eqtrdi ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 “ { 𝑈 , 𝑉 } ) = ( ( 𝐹𝑈 ) ∪ ( 𝐹𝑉 ) ) )
28 27 fveq2d ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 ( 𝐹 “ { 𝑈 , 𝑉 } ) ) = ( 𝐹 ‘ ( ( 𝐹𝑈 ) ∪ ( 𝐹𝑉 ) ) ) )
29 14 17 28 3eqtr3d ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋𝑉𝑋 ) → ( 𝐹 ‘ ( 𝑈𝑉 ) ) = ( 𝐹 ‘ ( ( 𝐹𝑈 ) ∪ ( 𝐹𝑉 ) ) ) )