Автомобіль мав подолати шлях завдовдки 140 км за 2 год. Деяку частину шляху він проіхав зі швидкістю 60 км/год, а решту шляху - зі швидкістю 75 км/год. Скільки кілометрів проїхав автомобіл зі швидкістю 60 км/год, якщо відомо, що до місця призначення він прибув вчасно?
0 және не знаю как гOTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
Write the correct preposition, then complete the
sentences for you.
Write the correct preposition, then complete the
sentences for you.
Write the correct preposition, then complete the
sentences for you.
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
OTBET:
the afternoon, learn work
in lunchtime, I eat pizza and drink juice
in night, I watch TV or play mobile games
in weekend, I go to picnicin
Write the correct preposition, then complete the
sentences for you.
Write the correct preposition, then complete the
sentences for you.
Write the correct preposition, then complete the
sentences for you.
Write the correct preposition, then complete the
sentences for you.
Айару казак тілі ден 7ші тапсымадан 1 жұмбақты 2ші жұмбақты айтшы казак тілі ден 7ші тапсымадан 1 жұмбақты 2ші жұмбақты айтшы казак тілі ден 7ші тапсымадан 1 жұмбақты 2ші жұмбақты айтшы апай Саламатсызба апай Саламатсызба апай Саламатсызба апай Саламатсызба апай
tg α – tg β = tg (α – β) (1 + tg α tg β).
Получаем:
tg x tg 2x tg 3x = tg 3x – tg x + tg 4x – tg 2x,
tg x tg 2x tg 3x = tg 2x (1 + tg x tg 3x) + tg 2x (1 + tg 2x tg 4x),
tg 2x (1 + tg x tg 3x – tg x tg 3x + 1 + tg 2x tg 4x) = 0,
tg 2x = 0 или tg 2x tg 4x = –2.
С первым понятно, что делать. Второе:
tg 2x tg 4x = –2,
tg 2x · 2 tg 2x / (1 – tg² 2x) = –2,
tg² 2x = tg² 2x – 1.
Это равенство невозможно.
Все решения получаются из уравнения tg 2x = 0, то есть 2x = πn, x = πn/2. Значения с нечётными n не подходят (tg x и tg 3x не существуют) , значит, ответ x = πk. Возможно так