(а+1)^2 (а+1)
б) ------------ = ------
(а–1)(а+1) (а–1)
686.
5–2m 2m–5 1
а) -------------- = – -------------- = – --------
(2m–5)^2 (2m–5)^2 2m–5
(2n–1)^2 2n–1
б) ------------- = – ---------
–2(2n–1) 2
687.
15а^2(а^2b^2–1) (ab–1)(ab+1)
а) ------------------------- = ----------------- =
45a^3(ab+1) 3a(ab+1)
ab–1
= ---------
3a
18а^2b(a^2–4) 3a(a–2)(a+2)
б) ---------------------- = – ------------------ =
–24ab^2(a–2) 4b(a–2)
3a(a+2)
= ------------
4b
688.
(d+2)^2 d+2
a) ------------ = --------
7d(d+2) 7d
6р(q–3) 6p
б) ------------- = -------
(q–3)^2 q–3
√18 = √9 ·√2 = 3√2
√8 = √4 ·√2 = 2√2
√32 = √16 ·√2 = 4√2
3√2 + 2√2 + 4√2 = 9√2 = 9· 1,414 = 12, 726 ≈ 12,7
Ответ: 12,7
Если я не ошибаюсь 100.000 метров делим 1800 секунд =55 км\ч минус 20 км\ч ровно 35 км\ч