Metamath Proof Explorer


Theorem tposres3

Description: The transposition restricted to a set. (Contributed by Zhi Wang, 6-Oct-2025)

Ref Expression
Hypothesis tposres2.1 ( 𝜑 → ¬ ∅ ∈ ( dom 𝐹𝑅 ) )
Assertion tposres3 ( 𝜑 → ( tpos 𝐹𝑅 ) = tpos ( 𝐹 𝑅 ) )

Proof

Step Hyp Ref Expression
1 tposres2.1 ( 𝜑 → ¬ ∅ ∈ ( dom 𝐹𝑅 ) )
2 1 tposres2 ( 𝜑 → ( tpos 𝐹𝑅 ) = ( tpos 𝐹 𝑅 ) )
3 relcnv Rel dom ( 𝐹 𝑅 )
4 cnvf1o ( Rel dom ( 𝐹 𝑅 ) → ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) : dom ( 𝐹 𝑅 ) –1-1-onto dom ( 𝐹 𝑅 ) )
5 3 4 ax-mp ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) : dom ( 𝐹 𝑅 ) –1-1-onto dom ( 𝐹 𝑅 )
6 f1ofo ( ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) : dom ( 𝐹 𝑅 ) –1-1-onto dom ( 𝐹 𝑅 ) → ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) : dom ( 𝐹 𝑅 ) –onto dom ( 𝐹 𝑅 ) )
7 5 6 ax-mp ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) : dom ( 𝐹 𝑅 ) –onto dom ( 𝐹 𝑅 )
8 forn ( ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) : dom ( 𝐹 𝑅 ) –onto dom ( 𝐹 𝑅 ) → ran ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) = dom ( 𝐹 𝑅 ) )
9 7 8 ax-mp ran ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) = dom ( 𝐹 𝑅 )
10 cnvcnvss dom ( 𝐹 𝑅 ) ⊆ dom ( 𝐹 𝑅 )
11 resdmss dom ( 𝐹 𝑅 ) ⊆ 𝑅
12 10 11 sstri dom ( 𝐹 𝑅 ) ⊆ 𝑅
13 9 12 eqsstri ran ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ⊆ 𝑅
14 cores ( ran ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ⊆ 𝑅 → ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) = ( 𝐹 ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) )
15 13 14 ax-mp ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) = ( 𝐹 ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) )
16 dftpos6 tpos ( 𝐹 𝑅 ) = ( ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) ∪ ( { ∅ } × ( ( 𝐹 𝑅 ) “ { ∅ } ) ) )
17 ressn ( ( 𝐹 𝑅 ) ↾ { ∅ } ) = ( { ∅ } × ( ( 𝐹 𝑅 ) “ { ∅ } ) )
18 resres ( ( 𝐹 𝑅 ) ↾ { ∅ } ) = ( 𝐹 ↾ ( 𝑅 ∩ { ∅ } ) )
19 relcnv Rel 𝑅
20 0nelrel0 ( Rel 𝑅 → ¬ ∅ ∈ 𝑅 )
21 19 20 ax-mp ¬ ∅ ∈ 𝑅
22 disjsn ( ( 𝑅 ∩ { ∅ } ) = ∅ ↔ ¬ ∅ ∈ 𝑅 )
23 21 22 mpbir ( 𝑅 ∩ { ∅ } ) = ∅
24 23 reseq2i ( 𝐹 ↾ ( 𝑅 ∩ { ∅ } ) ) = ( 𝐹 ↾ ∅ )
25 res0 ( 𝐹 ↾ ∅ ) = ∅
26 18 24 25 3eqtri ( ( 𝐹 𝑅 ) ↾ { ∅ } ) = ∅
27 17 26 eqtr3i ( { ∅ } × ( ( 𝐹 𝑅 ) “ { ∅ } ) ) = ∅
28 27 uneq2i ( ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) ∪ ( { ∅ } × ( ( 𝐹 𝑅 ) “ { ∅ } ) ) ) = ( ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) ∪ ∅ )
29 un0 ( ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) ) ∪ ∅ ) = ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) )
30 16 28 29 3eqtri tpos ( 𝐹 𝑅 ) = ( ( 𝐹 𝑅 ) ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) )
31 tposrescnv ( tpos 𝐹 𝑅 ) = ( 𝐹 ∘ ( 𝑥 dom ( 𝐹 𝑅 ) ↦ { 𝑥 } ) )
32 15 30 31 3eqtr4ri ( tpos 𝐹 𝑅 ) = tpos ( 𝐹 𝑅 )
33 2 32 eqtrdi ( 𝜑 → ( tpos 𝐹𝑅 ) = tpos ( 𝐹 𝑅 ) )