| Step | Hyp | Ref
 | Expression | 
| 1 |   | funfn 5288 | 
. . 3
⊢ (Fun
𝐹 ↔ 𝐹 Fn dom 𝐹) | 
| 2 |   | elin 3346 | 
. . . . . . . . 9
⊢ (𝑥 ∈ (𝐵 ∩ dom 𝐹) ↔ (𝑥 ∈ 𝐵 ∧ 𝑥 ∈ dom 𝐹)) | 
| 3 |   | ancom 266 | 
. . . . . . . . 9
⊢ ((𝑥 ∈ 𝐵 ∧ 𝑥 ∈ dom 𝐹) ↔ (𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵)) | 
| 4 | 2, 3 | bitri 184 | 
. . . . . . . 8
⊢ (𝑥 ∈ (𝐵 ∩ dom 𝐹) ↔ (𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵)) | 
| 5 | 4 | anbi1i 458 | 
. . . . . . 7
⊢ ((𝑥 ∈ (𝐵 ∩ dom 𝐹) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴) ↔ ((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴)) | 
| 6 |   | fvres 5582 | 
. . . . . . . . . 10
⊢ (𝑥 ∈ 𝐵 → ((𝐹 ↾ 𝐵)‘𝑥) = (𝐹‘𝑥)) | 
| 7 | 6 | eleq1d 2265 | 
. . . . . . . . 9
⊢ (𝑥 ∈ 𝐵 → (((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴 ↔ (𝐹‘𝑥) ∈ 𝐴)) | 
| 8 | 7 | adantl 277 | 
. . . . . . . 8
⊢ ((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) → (((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴 ↔ (𝐹‘𝑥) ∈ 𝐴)) | 
| 9 | 8 | pm5.32i 454 | 
. . . . . . 7
⊢ (((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴) ↔ ((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) ∧ (𝐹‘𝑥) ∈ 𝐴)) | 
| 10 | 5, 9 | bitri 184 | 
. . . . . 6
⊢ ((𝑥 ∈ (𝐵 ∩ dom 𝐹) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴) ↔ ((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) ∧ (𝐹‘𝑥) ∈ 𝐴)) | 
| 11 | 10 | a1i 9 | 
. . . . 5
⊢ (𝐹 Fn dom 𝐹 → ((𝑥 ∈ (𝐵 ∩ dom 𝐹) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴) ↔ ((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) ∧ (𝐹‘𝑥) ∈ 𝐴))) | 
| 12 |   | an32 562 | 
. . . . 5
⊢ (((𝑥 ∈ dom 𝐹 ∧ 𝑥 ∈ 𝐵) ∧ (𝐹‘𝑥) ∈ 𝐴) ↔ ((𝑥 ∈ dom 𝐹 ∧ (𝐹‘𝑥) ∈ 𝐴) ∧ 𝑥 ∈ 𝐵)) | 
| 13 | 11, 12 | bitrdi 196 | 
. . . 4
⊢ (𝐹 Fn dom 𝐹 → ((𝑥 ∈ (𝐵 ∩ dom 𝐹) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴) ↔ ((𝑥 ∈ dom 𝐹 ∧ (𝐹‘𝑥) ∈ 𝐴) ∧ 𝑥 ∈ 𝐵))) | 
| 14 |   | fnfun 5355 | 
. . . . . . . 8
⊢ (𝐹 Fn dom 𝐹 → Fun 𝐹) | 
| 15 |   | funres 5299 | 
. . . . . . . 8
⊢ (Fun
𝐹 → Fun (𝐹 ↾ 𝐵)) | 
| 16 | 14, 15 | syl 14 | 
. . . . . . 7
⊢ (𝐹 Fn dom 𝐹 → Fun (𝐹 ↾ 𝐵)) | 
| 17 |   | dmres 4967 | 
. . . . . . 7
⊢ dom
(𝐹 ↾ 𝐵) = (𝐵 ∩ dom 𝐹) | 
| 18 | 16, 17 | jctir 313 | 
. . . . . 6
⊢ (𝐹 Fn dom 𝐹 → (Fun (𝐹 ↾ 𝐵) ∧ dom (𝐹 ↾ 𝐵) = (𝐵 ∩ dom 𝐹))) | 
| 19 |   | df-fn 5261 | 
. . . . . 6
⊢ ((𝐹 ↾ 𝐵) Fn (𝐵 ∩ dom 𝐹) ↔ (Fun (𝐹 ↾ 𝐵) ∧ dom (𝐹 ↾ 𝐵) = (𝐵 ∩ dom 𝐹))) | 
| 20 | 18, 19 | sylibr 134 | 
. . . . 5
⊢ (𝐹 Fn dom 𝐹 → (𝐹 ↾ 𝐵) Fn (𝐵 ∩ dom 𝐹)) | 
| 21 |   | elpreima 5681 | 
. . . . 5
⊢ ((𝐹 ↾ 𝐵) Fn (𝐵 ∩ dom 𝐹) → (𝑥 ∈ (◡(𝐹 ↾ 𝐵) “ 𝐴) ↔ (𝑥 ∈ (𝐵 ∩ dom 𝐹) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴))) | 
| 22 | 20, 21 | syl 14 | 
. . . 4
⊢ (𝐹 Fn dom 𝐹 → (𝑥 ∈ (◡(𝐹 ↾ 𝐵) “ 𝐴) ↔ (𝑥 ∈ (𝐵 ∩ dom 𝐹) ∧ ((𝐹 ↾ 𝐵)‘𝑥) ∈ 𝐴))) | 
| 23 |   | elin 3346 | 
. . . . 5
⊢ (𝑥 ∈ ((◡𝐹 “ 𝐴) ∩ 𝐵) ↔ (𝑥 ∈ (◡𝐹 “ 𝐴) ∧ 𝑥 ∈ 𝐵)) | 
| 24 |   | elpreima 5681 | 
. . . . . 6
⊢ (𝐹 Fn dom 𝐹 → (𝑥 ∈ (◡𝐹 “ 𝐴) ↔ (𝑥 ∈ dom 𝐹 ∧ (𝐹‘𝑥) ∈ 𝐴))) | 
| 25 | 24 | anbi1d 465 | 
. . . . 5
⊢ (𝐹 Fn dom 𝐹 → ((𝑥 ∈ (◡𝐹 “ 𝐴) ∧ 𝑥 ∈ 𝐵) ↔ ((𝑥 ∈ dom 𝐹 ∧ (𝐹‘𝑥) ∈ 𝐴) ∧ 𝑥 ∈ 𝐵))) | 
| 26 | 23, 25 | bitrid 192 | 
. . . 4
⊢ (𝐹 Fn dom 𝐹 → (𝑥 ∈ ((◡𝐹 “ 𝐴) ∩ 𝐵) ↔ ((𝑥 ∈ dom 𝐹 ∧ (𝐹‘𝑥) ∈ 𝐴) ∧ 𝑥 ∈ 𝐵))) | 
| 27 | 13, 22, 26 | 3bitr4d 220 | 
. . 3
⊢ (𝐹 Fn dom 𝐹 → (𝑥 ∈ (◡(𝐹 ↾ 𝐵) “ 𝐴) ↔ 𝑥 ∈ ((◡𝐹 “ 𝐴) ∩ 𝐵))) | 
| 28 | 1, 27 | sylbi 121 | 
. 2
⊢ (Fun
𝐹 → (𝑥 ∈ (◡(𝐹 ↾ 𝐵) “ 𝐴) ↔ 𝑥 ∈ ((◡𝐹 “ 𝐴) ∩ 𝐵))) | 
| 29 | 28 | eqrdv 2194 | 
1
⊢ (Fun
𝐹 → (◡(𝐹 ↾ 𝐵) “ 𝐴) = ((◡𝐹 “ 𝐴) ∩ 𝐵)) |