| 0 < j, i1 < 0 ⊦ rational(i1 * i, i1 * j) = rational(i, j), i1 = 0 |
⊦ j < 0 → rational(i, j) = rational(~ i, abs(j))
i1 * j < 0, 0 < j, i1 < 0 ⊦ rational(~(i1 * i), abs(i1 * j)) = rational(i, j), i1 = 0
Used simplifier rules: ⊦ 0 < i → (i * j < 0 ↔ j < 0);% ⊦ ¬ i < j ↔ j ≤ i;% ⊦ i ≠ j → (i ≤ j ↔ i < j);% ⊦ i < j → ¬ j < i;% ⊦ i * j * j0 = (i * j) * j0;% ⊦ i * j = j * i; Used terms: i1 * j, i1 * i