15. Множення раціональних чисел - 17. Ділення » 623

Виконай дії. а) –17/28 • 5,6 + 21/4 • (–11/6) – (–13/8) • 4/11 = –17/28 • 28/5 + 9/4 • (–7/6) – (–11/8) • 4/11 = –17/5 + (–21/8) – (–4/8) = –17/5 + (–17/8) = –17 • (8/40 + 5/40) = –17 • 13/40 = –221/40 = –521/40. б) –2,2 • 3/11 + 51/7 • (–18/27) – 11/6 • (–2/35) = –11/5 • 3/11 + 36/7 • (–35/27) – 7/6 • (–2/35) = –3/5 + (–20/3) – (–1/15) = –9/15 + (–100/15) – (–1/15) = –108/15 = –71/5; в) ((–1/3)2 • (33/5) + 1/6 • (–24/5)) • (–33/4) = (1/9 • 18/5 + 1/6 • (–14/5)) • (–15/4) = (2/5 + (–7/15)) • (–15/4) = (6/15 + (–7/15)) • (–15/4) = –1/15 • (–15/4) = 1/4; г) –2/3 • (–3/5) + 2/7 • (–13/4) – (–1/5)3 • 81/3 = 2/5 + 2/7 • (–7/4) – (–1/125) • 25/3 = 2/5 + (–1/2) – (–1/15) = 12/30 + (–15/30) – (–2/30) = –1/30.