Proof of Theorem resdif
| Step | Hyp | Ref
 | Expression | 
| 1 |   | fofun 5481 | 
. . . . . 6
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → Fun (𝐹 ↾ 𝐴)) | 
| 2 |   | difss 3289 | 
. . . . . . 7
⊢ (𝐴 ∖ 𝐵) ⊆ 𝐴 | 
| 3 |   | fof 5480 | 
. . . . . . . 8
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → (𝐹 ↾ 𝐴):𝐴⟶𝐶) | 
| 4 |   | fdm 5413 | 
. . . . . . . 8
⊢ ((𝐹 ↾ 𝐴):𝐴⟶𝐶 → dom (𝐹 ↾ 𝐴) = 𝐴) | 
| 5 | 3, 4 | syl 14 | 
. . . . . . 7
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → dom (𝐹 ↾ 𝐴) = 𝐴) | 
| 6 | 2, 5 | sseqtrrid 3234 | 
. . . . . 6
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → (𝐴 ∖ 𝐵) ⊆ dom (𝐹 ↾ 𝐴)) | 
| 7 |   | fores 5490 | 
. . . . . 6
⊢ ((Fun
(𝐹 ↾ 𝐴) ∧ (𝐴 ∖ 𝐵) ⊆ dom (𝐹 ↾ 𝐴)) → ((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵))) | 
| 8 | 1, 6, 7 | syl2anc 411 | 
. . . . 5
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → ((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵))) | 
| 9 |   | resres 4958 | 
. . . . . . . 8
⊢ ((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)) = (𝐹 ↾ (𝐴 ∩ (𝐴 ∖ 𝐵))) | 
| 10 |   | indif 3406 | 
. . . . . . . . 9
⊢ (𝐴 ∩ (𝐴 ∖ 𝐵)) = (𝐴 ∖ 𝐵) | 
| 11 | 10 | reseq2i 4943 | 
. . . . . . . 8
⊢ (𝐹 ↾ (𝐴 ∩ (𝐴 ∖ 𝐵))) = (𝐹 ↾ (𝐴 ∖ 𝐵)) | 
| 12 | 9, 11 | eqtri 2217 | 
. . . . . . 7
⊢ ((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)) = (𝐹 ↾ (𝐴 ∖ 𝐵)) | 
| 13 |   | foeq1 5476 | 
. . . . . . 7
⊢ (((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)) = (𝐹 ↾ (𝐴 ∖ 𝐵)) → (((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)))) | 
| 14 | 12, 13 | ax-mp 5 | 
. . . . . 6
⊢ (((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵))) | 
| 15 | 12 | rneqi 4894 | 
. . . . . . . 8
⊢ ran
((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)) = ran (𝐹 ↾ (𝐴 ∖ 𝐵)) | 
| 16 |   | df-ima 4676 | 
. . . . . . . 8
⊢ ((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) = ran ((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)) | 
| 17 |   | df-ima 4676 | 
. . . . . . . 8
⊢ (𝐹 “ (𝐴 ∖ 𝐵)) = ran (𝐹 ↾ (𝐴 ∖ 𝐵)) | 
| 18 | 15, 16, 17 | 3eqtr4i 2227 | 
. . . . . . 7
⊢ ((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) = (𝐹 “ (𝐴 ∖ 𝐵)) | 
| 19 |   | foeq3 5478 | 
. . . . . . 7
⊢ (((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) = (𝐹 “ (𝐴 ∖ 𝐵)) → ((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→(𝐹 “ (𝐴 ∖ 𝐵)))) | 
| 20 | 18, 19 | ax-mp 5 | 
. . . . . 6
⊢ ((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→(𝐹 “ (𝐴 ∖ 𝐵))) | 
| 21 | 14, 20 | bitri 184 | 
. . . . 5
⊢ (((𝐹 ↾ 𝐴) ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→((𝐹 ↾ 𝐴) “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→(𝐹 “ (𝐴 ∖ 𝐵))) | 
| 22 | 8, 21 | sylib 122 | 
. . . 4
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→(𝐹 “ (𝐴 ∖ 𝐵))) | 
| 23 |   | funres11 5330 | 
. . . 4
⊢ (Fun
◡𝐹 → Fun ◡(𝐹 ↾ (𝐴 ∖ 𝐵))) | 
| 24 |   | dff1o3 5510 | 
. . . . 5
⊢ ((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐹 “ (𝐴 ∖ 𝐵)) ↔ ((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→(𝐹 “ (𝐴 ∖ 𝐵)) ∧ Fun ◡(𝐹 ↾ (𝐴 ∖ 𝐵)))) | 
| 25 | 24 | biimpri 133 | 
. . . 4
⊢ (((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–onto→(𝐹 “ (𝐴 ∖ 𝐵)) ∧ Fun ◡(𝐹 ↾ (𝐴 ∖ 𝐵))) → (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐹 “ (𝐴 ∖ 𝐵))) | 
| 26 | 22, 23, 25 | syl2anr 290 | 
. . 3
⊢ ((Fun
◡𝐹 ∧ (𝐹 ↾ 𝐴):𝐴–onto→𝐶) → (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐹 “ (𝐴 ∖ 𝐵))) | 
| 27 | 26 | 3adant3 1019 | 
. 2
⊢ ((Fun
◡𝐹 ∧ (𝐹 ↾ 𝐴):𝐴–onto→𝐶 ∧ (𝐹 ↾ 𝐵):𝐵–onto→𝐷) → (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐹 “ (𝐴 ∖ 𝐵))) | 
| 28 |   | df-ima 4676 | 
. . . . . . 7
⊢ (𝐹 “ 𝐴) = ran (𝐹 ↾ 𝐴) | 
| 29 |   | forn 5483 | 
. . . . . . 7
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → ran (𝐹 ↾ 𝐴) = 𝐶) | 
| 30 | 28, 29 | eqtrid 2241 | 
. . . . . 6
⊢ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 → (𝐹 “ 𝐴) = 𝐶) | 
| 31 |   | df-ima 4676 | 
. . . . . . 7
⊢ (𝐹 “ 𝐵) = ran (𝐹 ↾ 𝐵) | 
| 32 |   | forn 5483 | 
. . . . . . 7
⊢ ((𝐹 ↾ 𝐵):𝐵–onto→𝐷 → ran (𝐹 ↾ 𝐵) = 𝐷) | 
| 33 | 31, 32 | eqtrid 2241 | 
. . . . . 6
⊢ ((𝐹 ↾ 𝐵):𝐵–onto→𝐷 → (𝐹 “ 𝐵) = 𝐷) | 
| 34 | 30, 33 | anim12i 338 | 
. . . . 5
⊢ (((𝐹 ↾ 𝐴):𝐴–onto→𝐶 ∧ (𝐹 ↾ 𝐵):𝐵–onto→𝐷) → ((𝐹 “ 𝐴) = 𝐶 ∧ (𝐹 “ 𝐵) = 𝐷)) | 
| 35 |   | imadif 5338 | 
. . . . . 6
⊢ (Fun
◡𝐹 → (𝐹 “ (𝐴 ∖ 𝐵)) = ((𝐹 “ 𝐴) ∖ (𝐹 “ 𝐵))) | 
| 36 |   | difeq12 3276 | 
. . . . . 6
⊢ (((𝐹 “ 𝐴) = 𝐶 ∧ (𝐹 “ 𝐵) = 𝐷) → ((𝐹 “ 𝐴) ∖ (𝐹 “ 𝐵)) = (𝐶 ∖ 𝐷)) | 
| 37 | 35, 36 | sylan9eq 2249 | 
. . . . 5
⊢ ((Fun
◡𝐹 ∧ ((𝐹 “ 𝐴) = 𝐶 ∧ (𝐹 “ 𝐵) = 𝐷)) → (𝐹 “ (𝐴 ∖ 𝐵)) = (𝐶 ∖ 𝐷)) | 
| 38 | 34, 37 | sylan2 286 | 
. . . 4
⊢ ((Fun
◡𝐹 ∧ ((𝐹 ↾ 𝐴):𝐴–onto→𝐶 ∧ (𝐹 ↾ 𝐵):𝐵–onto→𝐷)) → (𝐹 “ (𝐴 ∖ 𝐵)) = (𝐶 ∖ 𝐷)) | 
| 39 | 38 | 3impb 1201 | 
. . 3
⊢ ((Fun
◡𝐹 ∧ (𝐹 ↾ 𝐴):𝐴–onto→𝐶 ∧ (𝐹 ↾ 𝐵):𝐵–onto→𝐷) → (𝐹 “ (𝐴 ∖ 𝐵)) = (𝐶 ∖ 𝐷)) | 
| 40 |   | f1oeq3 5494 | 
. . 3
⊢ ((𝐹 “ (𝐴 ∖ 𝐵)) = (𝐶 ∖ 𝐷) → ((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐹 “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐶 ∖ 𝐷))) | 
| 41 | 39, 40 | syl 14 | 
. 2
⊢ ((Fun
◡𝐹 ∧ (𝐹 ↾ 𝐴):𝐴–onto→𝐶 ∧ (𝐹 ↾ 𝐵):𝐵–onto→𝐷) → ((𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐹 “ (𝐴 ∖ 𝐵)) ↔ (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐶 ∖ 𝐷))) | 
| 42 | 27, 41 | mpbid 147 | 
1
⊢ ((Fun
◡𝐹 ∧ (𝐹 ↾ 𝐴):𝐴–onto→𝐶 ∧ (𝐹 ↾ 𝐵):𝐵–onto→𝐷) → (𝐹 ↾ (𝐴 ∖ 𝐵)):(𝐴 ∖ 𝐵)–1-1-onto→(𝐶 ∖ 𝐷)) |