Proof of Theorem dmrnxp
| Step | Hyp | Ref
| Expression |
| 1 | | simpl 483 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → 𝑅 = (𝐴 × 𝐵)) |
| 2 | | nne 2938 |
. . . . . . 7
⊢ (¬
𝐴 ≠ ∅ ↔ 𝐴 = ∅) |
| 3 | 2 | bilani 505 |
. . . . . 6
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → 𝐴 = ∅) |
| 4 | 3 | xpeq1d 5647 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → (𝐴 × 𝐵) = (∅ × 𝐵)) |
| 5 | | 0xp 5717 |
. . . . 5
⊢ (∅
× 𝐵) =
∅ |
| 6 | 4, 5 | eqtrdi 2790 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → (𝐴 × 𝐵) = ∅) |
| 7 | 1, 6 | eqtrd 2774 |
. . 3
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → 𝑅 = ∅) |
| 8 | 7 | dmeqd 5847 |
. . . . . 6
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → dom 𝑅 = dom ∅) |
| 9 | | dm0 5862 |
. . . . . 6
⊢ dom
∅ = ∅ |
| 10 | 8, 9 | eqtrdi 2790 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → dom 𝑅 = ∅) |
| 11 | 7 | rneqd 5880 |
. . . . . 6
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → ran 𝑅 = ran ∅) |
| 12 | | rn0 5868 |
. . . . . 6
⊢ ran
∅ = ∅ |
| 13 | 11, 12 | eqtrdi 2790 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → ran 𝑅 = ∅) |
| 14 | 10, 13 | xpeq12d 5649 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → (dom 𝑅 × ran 𝑅) = (∅ ×
∅)) |
| 15 | | 0xp 5717 |
. . . 4
⊢ (∅
× ∅) = ∅ |
| 16 | 14, 15 | eqtrdi 2790 |
. . 3
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → (dom 𝑅 × ran 𝑅) = ∅) |
| 17 | 7, 16 | eqtr4d 2777 |
. 2
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐴 ≠ ∅) → 𝑅 = (dom 𝑅 × ran 𝑅)) |
| 18 | | simpl 483 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → 𝑅 = (𝐴 × 𝐵)) |
| 19 | | nne 2938 |
. . . . . . 7
⊢ (¬
𝐵 ≠ ∅ ↔ 𝐵 = ∅) |
| 20 | 19 | bilani 505 |
. . . . . 6
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → 𝐵 = ∅) |
| 21 | 20 | xpeq2d 5648 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → (𝐴 × 𝐵) = (𝐴 × ∅)) |
| 22 | | xp0 5718 |
. . . . 5
⊢ (𝐴 × ∅) =
∅ |
| 23 | 21, 22 | eqtrdi 2790 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → (𝐴 × 𝐵) = ∅) |
| 24 | 18, 23 | eqtrd 2774 |
. . 3
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → 𝑅 = ∅) |
| 25 | 24 | dmeqd 5847 |
. . . . . 6
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → dom 𝑅 = dom ∅) |
| 26 | 25, 9 | eqtrdi 2790 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → dom 𝑅 = ∅) |
| 27 | 24 | rneqd 5880 |
. . . . . 6
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → ran 𝑅 = ran ∅) |
| 28 | 27, 12 | eqtrdi 2790 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → ran 𝑅 = ∅) |
| 29 | 26, 28 | xpeq12d 5649 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → (dom 𝑅 × ran 𝑅) = (∅ ×
∅)) |
| 30 | 29, 15 | eqtrdi 2790 |
. . 3
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → (dom 𝑅 × ran 𝑅) = ∅) |
| 31 | 24, 30 | eqtr4d 2777 |
. 2
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ ¬ 𝐵 ≠ ∅) → 𝑅 = (dom 𝑅 × ran 𝑅)) |
| 32 | | simpl 483 |
. . 3
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → 𝑅 = (𝐴 × 𝐵)) |
| 33 | 32 | dmeqd 5847 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → dom 𝑅 = dom (𝐴 × 𝐵)) |
| 34 | | dmxp 5871 |
. . . . . 6
⊢ (𝐵 ≠ ∅ → dom (𝐴 × 𝐵) = 𝐴) |
| 35 | 34 | ad2antll 735 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → dom (𝐴 × 𝐵) = 𝐴) |
| 36 | 33, 35 | eqtrd 2774 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → dom 𝑅 = 𝐴) |
| 37 | 32 | rneqd 5880 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → ran 𝑅 = ran (𝐴 × 𝐵)) |
| 38 | | rnxp 6121 |
. . . . . 6
⊢ (𝐴 ≠ ∅ → ran (𝐴 × 𝐵) = 𝐵) |
| 39 | 38 | ad2antrl 734 |
. . . . 5
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → ran (𝐴 × 𝐵) = 𝐵) |
| 40 | 37, 39 | eqtrd 2774 |
. . . 4
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → ran 𝑅 = 𝐵) |
| 41 | 36, 40 | xpeq12d 5649 |
. . 3
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → (dom 𝑅 × ran 𝑅) = (𝐴 × 𝐵)) |
| 42 | 32, 41 | eqtr4d 2777 |
. 2
⊢ ((𝑅 = (𝐴 × 𝐵) ∧ (𝐴 ≠ ∅ ∧ 𝐵 ≠ ∅)) → 𝑅 = (dom 𝑅 × ran 𝑅)) |
| 43 | 17, 31, 42 | pm2.61dda 820 |
1
⊢ (𝑅 = (𝐴 × 𝐵) → 𝑅 = (dom 𝑅 × ran 𝑅)) |