Description: The transposition restricted to a relation. (Contributed by Zhi Wang, 6-Oct-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | tposres | ⊢ ( Rel 𝑅 → ( tpos 𝐹 ↾ 𝑅 ) = tpos ( 𝐹 ↾ ◡ 𝑅 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 0nelrel0 | ⊢ ( Rel 𝑅 → ¬ ∅ ∈ 𝑅 ) | |
| 2 | nel2nelin | ⊢ ( ¬ ∅ ∈ 𝑅 → ¬ ∅ ∈ ( dom 𝐹 ∩ 𝑅 ) ) | |
| 3 | 1 2 | syl | ⊢ ( Rel 𝑅 → ¬ ∅ ∈ ( dom 𝐹 ∩ 𝑅 ) ) |
| 4 | 3 | tposres3 | ⊢ ( Rel 𝑅 → ( tpos 𝐹 ↾ 𝑅 ) = tpos ( 𝐹 ↾ ◡ 𝑅 ) ) |