| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | dfse2 6117 | . . . . . . . . 9
⊢ (𝑅 Se 𝐴 ↔ ∀𝑧 ∈ 𝐴 (𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V) | 
| 2 | 1 | biimpi 216 | . . . . . . . 8
⊢ (𝑅 Se 𝐴 → ∀𝑧 ∈ 𝐴 (𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V) | 
| 3 | 2 | r19.21bi 3250 | . . . . . . 7
⊢ ((𝑅 Se 𝐴 ∧ 𝑧 ∈ 𝐴) → (𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V) | 
| 4 | 3 | expcom 413 | . . . . . 6
⊢ (𝑧 ∈ 𝐴 → (𝑅 Se 𝐴 → (𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V)) | 
| 5 | 4 | adantl 481 | . . . . 5
⊢ ((𝜑 ∧ 𝑧 ∈ 𝐴) → (𝑅 Se 𝐴 → (𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V)) | 
| 6 |  | imaeq2 6073 | . . . . . . . . . . 11
⊢ (𝑥 = (𝐴 ∩ (◡𝑅 “ {𝑧})) → (𝐻 “ 𝑥) = (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧})))) | 
| 7 | 6 | eleq1d 2825 | . . . . . . . . . 10
⊢ (𝑥 = (𝐴 ∩ (◡𝑅 “ {𝑧})) → ((𝐻 “ 𝑥) ∈ V ↔ (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) ∈ V)) | 
| 8 | 7 | imbi2d 340 | . . . . . . . . 9
⊢ (𝑥 = (𝐴 ∩ (◡𝑅 “ {𝑧})) → ((𝜑 → (𝐻 “ 𝑥) ∈ V) ↔ (𝜑 → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) ∈ V))) | 
| 9 |  | isofrlem.2 | . . . . . . . . 9
⊢ (𝜑 → (𝐻 “ 𝑥) ∈ V) | 
| 10 | 8, 9 | vtoclg 3553 | . . . . . . . 8
⊢ ((𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V → (𝜑 → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) ∈ V)) | 
| 11 | 10 | com12 32 | . . . . . . 7
⊢ (𝜑 → ((𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) ∈ V)) | 
| 12 | 11 | adantr 480 | . . . . . 6
⊢ ((𝜑 ∧ 𝑧 ∈ 𝐴) → ((𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) ∈ V)) | 
| 13 |  | isofrlem.1 | . . . . . . . 8
⊢ (𝜑 → 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)) | 
| 14 |  | isoini 7359 | . . . . . . . 8
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝑧 ∈ 𝐴) → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) = (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)}))) | 
| 15 | 13, 14 | sylan 580 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑧 ∈ 𝐴) → (𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) = (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)}))) | 
| 16 | 15 | eleq1d 2825 | . . . . . 6
⊢ ((𝜑 ∧ 𝑧 ∈ 𝐴) → ((𝐻 “ (𝐴 ∩ (◡𝑅 “ {𝑧}))) ∈ V ↔ (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 17 | 12, 16 | sylibd 239 | . . . . 5
⊢ ((𝜑 ∧ 𝑧 ∈ 𝐴) → ((𝐴 ∩ (◡𝑅 “ {𝑧})) ∈ V → (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 18 | 5, 17 | syld 47 | . . . 4
⊢ ((𝜑 ∧ 𝑧 ∈ 𝐴) → (𝑅 Se 𝐴 → (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 19 | 18 | ralrimdva 3153 | . . 3
⊢ (𝜑 → (𝑅 Se 𝐴 → ∀𝑧 ∈ 𝐴 (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 20 |  | isof1o 7344 | . . . . 5
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → 𝐻:𝐴–1-1-onto→𝐵) | 
| 21 |  | f1ofn 6848 | . . . . 5
⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻 Fn 𝐴) | 
| 22 |  | sneq 4635 | . . . . . . . . 9
⊢ (𝑦 = (𝐻‘𝑧) → {𝑦} = {(𝐻‘𝑧)}) | 
| 23 | 22 | imaeq2d 6077 | . . . . . . . 8
⊢ (𝑦 = (𝐻‘𝑧) → (◡𝑆 “ {𝑦}) = (◡𝑆 “ {(𝐻‘𝑧)})) | 
| 24 | 23 | ineq2d 4219 | . . . . . . 7
⊢ (𝑦 = (𝐻‘𝑧) → (𝐵 ∩ (◡𝑆 “ {𝑦})) = (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)}))) | 
| 25 | 24 | eleq1d 2825 | . . . . . 6
⊢ (𝑦 = (𝐻‘𝑧) → ((𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V ↔ (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 26 | 25 | ralrn 7107 | . . . . 5
⊢ (𝐻 Fn 𝐴 → (∀𝑦 ∈ ran 𝐻(𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V ↔ ∀𝑧 ∈ 𝐴 (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 27 | 13, 20, 21, 26 | 4syl 19 | . . . 4
⊢ (𝜑 → (∀𝑦 ∈ ran 𝐻(𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V ↔ ∀𝑧 ∈ 𝐴 (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V)) | 
| 28 |  | f1ofo 6854 | . . . . . 6
⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻:𝐴–onto→𝐵) | 
| 29 |  | forn 6822 | . . . . . 6
⊢ (𝐻:𝐴–onto→𝐵 → ran 𝐻 = 𝐵) | 
| 30 | 13, 20, 28, 29 | 4syl 19 | . . . . 5
⊢ (𝜑 → ran 𝐻 = 𝐵) | 
| 31 | 30 | raleqdv 3325 | . . . 4
⊢ (𝜑 → (∀𝑦 ∈ ran 𝐻(𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V ↔ ∀𝑦 ∈ 𝐵 (𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V)) | 
| 32 | 27, 31 | bitr3d 281 | . . 3
⊢ (𝜑 → (∀𝑧 ∈ 𝐴 (𝐵 ∩ (◡𝑆 “ {(𝐻‘𝑧)})) ∈ V ↔ ∀𝑦 ∈ 𝐵 (𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V)) | 
| 33 | 19, 32 | sylibd 239 | . 2
⊢ (𝜑 → (𝑅 Se 𝐴 → ∀𝑦 ∈ 𝐵 (𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V)) | 
| 34 |  | dfse2 6117 | . 2
⊢ (𝑆 Se 𝐵 ↔ ∀𝑦 ∈ 𝐵 (𝐵 ∩ (◡𝑆 “ {𝑦})) ∈ V) | 
| 35 | 33, 34 | imbitrrdi 252 | 1
⊢ (𝜑 → (𝑅 Se 𝐴 → 𝑆 Se 𝐵)) |