Proof of Theorem f1ocnvfv2
Step | Hyp | Ref
| Expression |
1 | | f1ococnv2 6889 |
. . . 4
⊢ (𝐹:𝐴–1-1-onto→𝐵 → (𝐹 ∘ ◡𝐹) = ( I ↾ 𝐵)) |
2 | 1 | fveq1d 6922 |
. . 3
⊢ (𝐹:𝐴–1-1-onto→𝐵 → ((𝐹 ∘ ◡𝐹)‘𝐶) = (( I ↾ 𝐵)‘𝐶)) |
3 | 2 | adantr 480 |
. 2
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐶 ∈ 𝐵) → ((𝐹 ∘ ◡𝐹)‘𝐶) = (( I ↾ 𝐵)‘𝐶)) |
4 | | f1ocnv 6874 |
. . . 4
⊢ (𝐹:𝐴–1-1-onto→𝐵 → ◡𝐹:𝐵–1-1-onto→𝐴) |
5 | | f1of 6862 |
. . . 4
⊢ (◡𝐹:𝐵–1-1-onto→𝐴 → ◡𝐹:𝐵⟶𝐴) |
6 | 4, 5 | syl 17 |
. . 3
⊢ (𝐹:𝐴–1-1-onto→𝐵 → ◡𝐹:𝐵⟶𝐴) |
7 | | fvco3 7021 |
. . 3
⊢ ((◡𝐹:𝐵⟶𝐴 ∧ 𝐶 ∈ 𝐵) → ((𝐹 ∘ ◡𝐹)‘𝐶) = (𝐹‘(◡𝐹‘𝐶))) |
8 | 6, 7 | sylan 579 |
. 2
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐶 ∈ 𝐵) → ((𝐹 ∘ ◡𝐹)‘𝐶) = (𝐹‘(◡𝐹‘𝐶))) |
9 | | fvresi 7207 |
. . 3
⊢ (𝐶 ∈ 𝐵 → (( I ↾ 𝐵)‘𝐶) = 𝐶) |
10 | 9 | adantl 481 |
. 2
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐶 ∈ 𝐵) → (( I ↾ 𝐵)‘𝐶) = 𝐶) |
11 | 3, 8, 10 | 3eqtr3d 2788 |
1
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐶 ∈ 𝐵) → (𝐹‘(◡𝐹‘𝐶)) = 𝐶) |