| Step | Hyp | Ref
 | Expression | 
| 1 |   | dmres 4967 | 
. . . . 5
⊢ dom
(𝐹 ↾ 𝐴) = (𝐴 ∩ dom 𝐹) | 
| 2 | 1 | imaeq2i 5007 | 
. . . 4
⊢ (𝐹 “ dom (𝐹 ↾ 𝐴)) = (𝐹 “ (𝐴 ∩ dom 𝐹)) | 
| 3 |   | imadmres 5162 | 
. . . 4
⊢ (𝐹 “ dom (𝐹 ↾ 𝐴)) = (𝐹 “ 𝐴) | 
| 4 | 2, 3 | eqtr3i 2219 | 
. . 3
⊢ (𝐹 “ (𝐴 ∩ dom 𝐹)) = (𝐹 “ 𝐴) | 
| 5 | 4 | sseq2i 3210 | 
. 2
⊢ (𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹)) ↔ 𝐵 ⊆ (𝐹 “ 𝐴)) | 
| 6 |   | ssrab2 3268 | 
. . . 4
⊢ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ⊆ (𝐴 ∩ dom 𝐹) | 
| 7 |   | ssel2 3178 | 
. . . . . . . . 9
⊢ ((𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹)) ∧ 𝑧 ∈ 𝐵) → 𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹))) | 
| 8 | 7 | adantll 476 | 
. . . . . . . 8
⊢ (((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) ∧ 𝑧 ∈ 𝐵) → 𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹))) | 
| 9 |   | fvelima 5612 | 
. . . . . . . . . . . 12
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹))) → ∃𝑤 ∈ (𝐴 ∩ dom 𝐹)(𝐹‘𝑤) = 𝑧) | 
| 10 | 9 | ex 115 | 
. . . . . . . . . . 11
⊢ (Fun
𝐹 → (𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹)) → ∃𝑤 ∈ (𝐴 ∩ dom 𝐹)(𝐹‘𝑤) = 𝑧)) | 
| 11 | 10 | adantr 276 | 
. . . . . . . . . 10
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ 𝐵) → (𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹)) → ∃𝑤 ∈ (𝐴 ∩ dom 𝐹)(𝐹‘𝑤) = 𝑧)) | 
| 12 |   | eleq1a 2268 | 
. . . . . . . . . . . . . . . 16
⊢ (𝑧 ∈ 𝐵 → ((𝐹‘𝑤) = 𝑧 → (𝐹‘𝑤) ∈ 𝐵)) | 
| 13 | 12 | anim2d 337 | 
. . . . . . . . . . . . . . 15
⊢ (𝑧 ∈ 𝐵 → ((𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) = 𝑧) → (𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) ∈ 𝐵))) | 
| 14 |   | fveq2 5558 | 
. . . . . . . . . . . . . . . . 17
⊢ (𝑦 = 𝑤 → (𝐹‘𝑦) = (𝐹‘𝑤)) | 
| 15 | 14 | eleq1d 2265 | 
. . . . . . . . . . . . . . . 16
⊢ (𝑦 = 𝑤 → ((𝐹‘𝑦) ∈ 𝐵 ↔ (𝐹‘𝑤) ∈ 𝐵)) | 
| 16 | 15 | elrab 2920 | 
. . . . . . . . . . . . . . 15
⊢ (𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ↔ (𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) ∈ 𝐵)) | 
| 17 | 13, 16 | imbitrrdi 162 | 
. . . . . . . . . . . . . 14
⊢ (𝑧 ∈ 𝐵 → ((𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) = 𝑧) → 𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})) | 
| 18 |   | simpr 110 | 
. . . . . . . . . . . . . . 15
⊢ ((𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) = 𝑧) → (𝐹‘𝑤) = 𝑧) | 
| 19 | 18 | a1i 9 | 
. . . . . . . . . . . . . 14
⊢ (𝑧 ∈ 𝐵 → ((𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) = 𝑧) → (𝐹‘𝑤) = 𝑧)) | 
| 20 | 17, 19 | jcad 307 | 
. . . . . . . . . . . . 13
⊢ (𝑧 ∈ 𝐵 → ((𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) = 𝑧) → (𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ∧ (𝐹‘𝑤) = 𝑧))) | 
| 21 | 20 | reximdv2 2596 | 
. . . . . . . . . . . 12
⊢ (𝑧 ∈ 𝐵 → (∃𝑤 ∈ (𝐴 ∩ dom 𝐹)(𝐹‘𝑤) = 𝑧 → ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 22 | 21 | adantl 277 | 
. . . . . . . . . . 11
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ 𝐵) → (∃𝑤 ∈ (𝐴 ∩ dom 𝐹)(𝐹‘𝑤) = 𝑧 → ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 23 |   | funfn 5288 | 
. . . . . . . . . . . . 13
⊢ (Fun
𝐹 ↔ 𝐹 Fn dom 𝐹) | 
| 24 |   | inss2 3384 | 
. . . . . . . . . . . . . . 15
⊢ (𝐴 ∩ dom 𝐹) ⊆ dom 𝐹 | 
| 25 | 6, 24 | sstri 3192 | 
. . . . . . . . . . . . . 14
⊢ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ⊆ dom 𝐹 | 
| 26 |   | fvelimab 5617 | 
. . . . . . . . . . . . . 14
⊢ ((𝐹 Fn dom 𝐹 ∧ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ⊆ dom 𝐹) → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) ↔ ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 27 | 25, 26 | mpan2 425 | 
. . . . . . . . . . . . 13
⊢ (𝐹 Fn dom 𝐹 → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) ↔ ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 28 | 23, 27 | sylbi 121 | 
. . . . . . . . . . . 12
⊢ (Fun
𝐹 → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) ↔ ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 29 | 28 | adantr 276 | 
. . . . . . . . . . 11
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ 𝐵) → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) ↔ ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 30 | 22, 29 | sylibrd 169 | 
. . . . . . . . . 10
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ 𝐵) → (∃𝑤 ∈ (𝐴 ∩ dom 𝐹)(𝐹‘𝑤) = 𝑧 → 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}))) | 
| 31 | 11, 30 | syld 45 | 
. . . . . . . . 9
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ 𝐵) → (𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹)) → 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}))) | 
| 32 | 31 | adantlr 477 | 
. . . . . . . 8
⊢ (((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) ∧ 𝑧 ∈ 𝐵) → (𝑧 ∈ (𝐹 “ (𝐴 ∩ dom 𝐹)) → 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}))) | 
| 33 | 8, 32 | mpd 13 | 
. . . . . . 7
⊢ (((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) ∧ 𝑧 ∈ 𝐵) → 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})) | 
| 34 | 33 | ex 115 | 
. . . . . 6
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) → (𝑧 ∈ 𝐵 → 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}))) | 
| 35 |   | fvelima 5612 | 
. . . . . . . . 9
⊢ ((Fun
𝐹 ∧ 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})) → ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧) | 
| 36 | 35 | ex 115 | 
. . . . . . . 8
⊢ (Fun
𝐹 → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) → ∃𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧)) | 
| 37 |   | eleq1 2259 | 
. . . . . . . . . . . 12
⊢ ((𝐹‘𝑤) = 𝑧 → ((𝐹‘𝑤) ∈ 𝐵 ↔ 𝑧 ∈ 𝐵)) | 
| 38 | 37 | biimpcd 159 | 
. . . . . . . . . . 11
⊢ ((𝐹‘𝑤) ∈ 𝐵 → ((𝐹‘𝑤) = 𝑧 → 𝑧 ∈ 𝐵)) | 
| 39 | 38 | adantl 277 | 
. . . . . . . . . 10
⊢ ((𝑤 ∈ (𝐴 ∩ dom 𝐹) ∧ (𝐹‘𝑤) ∈ 𝐵) → ((𝐹‘𝑤) = 𝑧 → 𝑧 ∈ 𝐵)) | 
| 40 | 16, 39 | sylbi 121 | 
. . . . . . . . 9
⊢ (𝑤 ∈ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} → ((𝐹‘𝑤) = 𝑧 → 𝑧 ∈ 𝐵)) | 
| 41 | 40 | rexlimiv 2608 | 
. . . . . . . 8
⊢
(∃𝑤 ∈
{𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} (𝐹‘𝑤) = 𝑧 → 𝑧 ∈ 𝐵) | 
| 42 | 36, 41 | syl6 33 | 
. . . . . . 7
⊢ (Fun
𝐹 → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) → 𝑧 ∈ 𝐵)) | 
| 43 | 42 | adantr 276 | 
. . . . . 6
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) → (𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}) → 𝑧 ∈ 𝐵)) | 
| 44 | 34, 43 | impbid 129 | 
. . . . 5
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) → (𝑧 ∈ 𝐵 ↔ 𝑧 ∈ (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}))) | 
| 45 | 44 | eqrdv 2194 | 
. . . 4
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) → 𝐵 = (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})) | 
| 46 |   | ssimaex.1 | 
. . . . . . 7
⊢ 𝐴 ∈ V | 
| 47 | 46 | inex1 4167 | 
. . . . . 6
⊢ (𝐴 ∩ dom 𝐹) ∈ V | 
| 48 | 47 | rabex 4177 | 
. . . . 5
⊢ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ∈ V | 
| 49 |   | sseq1 3206 | 
. . . . . 6
⊢ (𝑥 = {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} → (𝑥 ⊆ (𝐴 ∩ dom 𝐹) ↔ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ⊆ (𝐴 ∩ dom 𝐹))) | 
| 50 |   | imaeq2 5005 | 
. . . . . . 7
⊢ (𝑥 = {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} → (𝐹 “ 𝑥) = (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})) | 
| 51 | 50 | eqeq2d 2208 | 
. . . . . 6
⊢ (𝑥 = {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} → (𝐵 = (𝐹 “ 𝑥) ↔ 𝐵 = (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵}))) | 
| 52 | 49, 51 | anbi12d 473 | 
. . . . 5
⊢ (𝑥 = {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} → ((𝑥 ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ 𝑥)) ↔ ({𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})))) | 
| 53 | 48, 52 | spcev 2859 | 
. . . 4
⊢ (({𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵} ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ {𝑦 ∈ (𝐴 ∩ dom 𝐹) ∣ (𝐹‘𝑦) ∈ 𝐵})) → ∃𝑥(𝑥 ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ 𝑥))) | 
| 54 | 6, 45, 53 | sylancr 414 | 
. . 3
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) → ∃𝑥(𝑥 ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ 𝑥))) | 
| 55 |   | inss1 3383 | 
. . . . . 6
⊢ (𝐴 ∩ dom 𝐹) ⊆ 𝐴 | 
| 56 |   | sstr 3191 | 
. . . . . 6
⊢ ((𝑥 ⊆ (𝐴 ∩ dom 𝐹) ∧ (𝐴 ∩ dom 𝐹) ⊆ 𝐴) → 𝑥 ⊆ 𝐴) | 
| 57 | 55, 56 | mpan2 425 | 
. . . . 5
⊢ (𝑥 ⊆ (𝐴 ∩ dom 𝐹) → 𝑥 ⊆ 𝐴) | 
| 58 | 57 | anim1i 340 | 
. . . 4
⊢ ((𝑥 ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ 𝑥)) → (𝑥 ⊆ 𝐴 ∧ 𝐵 = (𝐹 “ 𝑥))) | 
| 59 | 58 | eximi 1614 | 
. . 3
⊢
(∃𝑥(𝑥 ⊆ (𝐴 ∩ dom 𝐹) ∧ 𝐵 = (𝐹 “ 𝑥)) → ∃𝑥(𝑥 ⊆ 𝐴 ∧ 𝐵 = (𝐹 “ 𝑥))) | 
| 60 | 54, 59 | syl 14 | 
. 2
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ (𝐴 ∩ dom 𝐹))) → ∃𝑥(𝑥 ⊆ 𝐴 ∧ 𝐵 = (𝐹 “ 𝑥))) | 
| 61 | 5, 60 | sylan2br 288 | 
1
⊢ ((Fun
𝐹 ∧ 𝐵 ⊆ (𝐹 “ 𝐴)) → ∃𝑥(𝑥 ⊆ 𝐴 ∧ 𝐵 = (𝐹 “ 𝑥))) |