Odpowiedź:
3 i 1/5 * 1/2 - 5/7 * 1 i 2/5 = 16/5 * 1/2 - 5/7 * 7/5 = 8/5 - 1 = 1 i 3/5 - 1 = 3/5
1/5 * (3 i 3/7 - 2/7 * 5 i 1/2) = 1/5 * (3 i 3/7 - 2/7 * 11/2) = 1/5 * (3 i 3/7 - 11/7) = 1/5 * (3 i 3/7 - 1 i 4/7) = 1/5 * (2 i 10/7 - 1 i 4/7) = 1/5 * 1 i 6/7 = 1/5 * 13/7 = 13/35
