Proof of Theorem sbthlemi4
| Step | Hyp | Ref
 | Expression | 
| 1 |   | df-ima 4676 | 
. 2
⊢ (◡𝑔 “ (𝐴 ∖ ∪ 𝐷)) = ran (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷)) | 
| 2 |   | difss 3289 | 
. . . . . . . 8
⊢ (𝐵 ∖ (𝑓 “ ∪ 𝐷)) ⊆ 𝐵 | 
| 3 |   | sseq2 3207 | 
. . . . . . . 8
⊢ (dom
𝑔 = 𝐵 → ((𝐵 ∖ (𝑓 “ ∪ 𝐷)) ⊆ dom 𝑔 ↔ (𝐵 ∖ (𝑓 “ ∪ 𝐷)) ⊆ 𝐵)) | 
| 4 | 2, 3 | mpbiri 168 | 
. . . . . . 7
⊢ (dom
𝑔 = 𝐵 → (𝐵 ∖ (𝑓 “ ∪ 𝐷)) ⊆ dom 𝑔) | 
| 5 |   | ssdmres 4968 | 
. . . . . . 7
⊢ ((𝐵 ∖ (𝑓 “ ∪ 𝐷)) ⊆ dom 𝑔 ↔ dom (𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = (𝐵 ∖ (𝑓 “ ∪ 𝐷))) | 
| 6 | 4, 5 | sylib 122 | 
. . . . . 6
⊢ (dom
𝑔 = 𝐵 → dom (𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = (𝐵 ∖ (𝑓 “ ∪ 𝐷))) | 
| 7 |   | dfdm4 4858 | 
. . . . . 6
⊢ dom
(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = ran ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) | 
| 8 | 6, 7 | eqtr3di 2244 | 
. . . . 5
⊢ (dom
𝑔 = 𝐵 → (𝐵 ∖ (𝑓 “ ∪ 𝐷)) = ran ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷)))) | 
| 9 | 8 | adantr 276 | 
. . . 4
⊢ ((dom
𝑔 = 𝐵 ∧ ran 𝑔 ⊆ 𝐴) → (𝐵 ∖ (𝑓 “ ∪ 𝐷)) = ran ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷)))) | 
| 10 | 9 | 3ad2ant2 1021 | 
. . 3
⊢
((EXMID ∧ (dom 𝑔 = 𝐵 ∧ ran 𝑔 ⊆ 𝐴) ∧ Fun ◡𝑔) → (𝐵 ∖ (𝑓 “ ∪ 𝐷)) = ran ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷)))) | 
| 11 |   | funcnvres 5331 | 
. . . . . . 7
⊢ (Fun
◡𝑔 → ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = (◡𝑔 ↾ (𝑔 “ (𝐵 ∖ (𝑓 “ ∪ 𝐷))))) | 
| 12 | 11 | 3ad2ant3 1022 | 
. . . . . 6
⊢
((EXMID ∧ ran 𝑔 ⊆ 𝐴 ∧ Fun ◡𝑔) → ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = (◡𝑔 ↾ (𝑔 “ (𝐵 ∖ (𝑓 “ ∪ 𝐷))))) | 
| 13 |   | sbthlem.1 | 
. . . . . . . . 9
⊢ 𝐴 ∈ V | 
| 14 |   | sbthlem.2 | 
. . . . . . . . 9
⊢ 𝐷 = {𝑥 ∣ (𝑥 ⊆ 𝐴 ∧ (𝑔 “ (𝐵 ∖ (𝑓 “ 𝑥))) ⊆ (𝐴 ∖ 𝑥))} | 
| 15 | 13, 14 | sbthlemi3 7025 | 
. . . . . . . 8
⊢
((EXMID ∧ ran 𝑔 ⊆ 𝐴) → (𝑔 “ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = (𝐴 ∖ ∪ 𝐷)) | 
| 16 | 15 | reseq2d 4946 | 
. . . . . . 7
⊢
((EXMID ∧ ran 𝑔 ⊆ 𝐴) → (◡𝑔 ↾ (𝑔 “ (𝐵 ∖ (𝑓 “ ∪ 𝐷)))) = (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷))) | 
| 17 | 16 | 3adant3 1019 | 
. . . . . 6
⊢
((EXMID ∧ ran 𝑔 ⊆ 𝐴 ∧ Fun ◡𝑔) → (◡𝑔 ↾ (𝑔 “ (𝐵 ∖ (𝑓 “ ∪ 𝐷)))) = (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷))) | 
| 18 | 12, 17 | eqtrd 2229 | 
. . . . 5
⊢
((EXMID ∧ ran 𝑔 ⊆ 𝐴 ∧ Fun ◡𝑔) → ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷))) | 
| 19 | 18 | rneqd 4895 | 
. . . 4
⊢
((EXMID ∧ ran 𝑔 ⊆ 𝐴 ∧ Fun ◡𝑔) → ran ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = ran (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷))) | 
| 20 | 19 | 3adant2l 1234 | 
. . 3
⊢
((EXMID ∧ (dom 𝑔 = 𝐵 ∧ ran 𝑔 ⊆ 𝐴) ∧ Fun ◡𝑔) → ran ◡(𝑔 ↾ (𝐵 ∖ (𝑓 “ ∪ 𝐷))) = ran (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷))) | 
| 21 | 10, 20 | eqtrd 2229 | 
. 2
⊢
((EXMID ∧ (dom 𝑔 = 𝐵 ∧ ran 𝑔 ⊆ 𝐴) ∧ Fun ◡𝑔) → (𝐵 ∖ (𝑓 “ ∪ 𝐷)) = ran (◡𝑔 ↾ (𝐴 ∖ ∪ 𝐷))) | 
| 22 | 1, 21 | eqtr4id 2248 | 
1
⊢
((EXMID ∧ (dom 𝑔 = 𝐵 ∧ ran 𝑔 ⊆ 𝐴) ∧ Fun ◡𝑔) → (◡𝑔 “ (𝐴 ∖ ∪ 𝐷)) = (𝐵 ∖ (𝑓 “ ∪ 𝐷))) |