| Step |
Hyp |
Ref |
Expression |
| 1 |
|
marypha2lem.t |
⊢ 𝑇 = ∪ 𝑥 ∈ 𝐴 ( { 𝑥 } × ( 𝐹 ‘ 𝑥 ) ) |
| 2 |
|
iunss |
⊢ ( ∪ 𝑥 ∈ 𝐴 ( { 𝑥 } × ( 𝐹 ‘ 𝑥 ) ) ⊆ ( 𝐴 × ∪ ran 𝐹 ) ↔ ∀ 𝑥 ∈ 𝐴 ( { 𝑥 } × ( 𝐹 ‘ 𝑥 ) ) ⊆ ( 𝐴 × ∪ ran 𝐹 ) ) |
| 3 |
|
snssi |
⊢ ( 𝑥 ∈ 𝐴 → { 𝑥 } ⊆ 𝐴 ) |
| 4 |
|
fvssunirn |
⊢ ( 𝐹 ‘ 𝑥 ) ⊆ ∪ ran 𝐹 |
| 5 |
|
xpss12 |
⊢ ( ( { 𝑥 } ⊆ 𝐴 ∧ ( 𝐹 ‘ 𝑥 ) ⊆ ∪ ran 𝐹 ) → ( { 𝑥 } × ( 𝐹 ‘ 𝑥 ) ) ⊆ ( 𝐴 × ∪ ran 𝐹 ) ) |
| 6 |
3 4 5
|
sylancl |
⊢ ( 𝑥 ∈ 𝐴 → ( { 𝑥 } × ( 𝐹 ‘ 𝑥 ) ) ⊆ ( 𝐴 × ∪ ran 𝐹 ) ) |
| 7 |
2 6
|
mprgbir |
⊢ ∪ 𝑥 ∈ 𝐴 ( { 𝑥 } × ( 𝐹 ‘ 𝑥 ) ) ⊆ ( 𝐴 × ∪ ran 𝐹 ) |
| 8 |
1 7
|
eqsstri |
⊢ 𝑇 ⊆ ( 𝐴 × ∪ ran 𝐹 ) |