| j1 < 0 ⊦ rational(~ i1, abs(j1)) * rational(i2, j2) = rational(i1 * i2, j1 * j2), j2 = 0, j1 = 0, ¬ j1 < 0 ∧ ¬ j2 < 0 |
0 < j1, 0 < j2 ⊦ rational(i1, j1) * rational(i2, j2) = rational(i1 * i2, j1 * j2)
¬(0 < abs(j1) ∧ 0 < j2), j1 < 0 ⊦ rational(~ i1, abs(j1)) * rational(i2, j2) = rational(i1 * i2, j1 * j2), j2 = 0, j1 = 0, ¬ j1 < 0 ∧ ¬ j2 < 0
0 < abs(j1) ∧ 0 < j2, j1 < 0 ⊦ rational(~ i1 * i2, abs(j1) * j2) = rational(i1 * i2, j1 * j2), j2 = 0, j1 = 0, ¬ j1 < 0 ∧ ¬ j2 < 0
Used terms: j2, i2, abs(j1), ~ i1