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Вопрос по алгебре:
ОПРЕДЕЛИТЬ ЗНАК ВЫРАЖЕНИЯ: sin 7П/11* tg (-3П/7)* ctg 2
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Автор:
mccormick
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Ответ:
чтобы определить знак выражения - достаточно определить в какой четверти находится каждый из угловопорными точками будут точки [0;π/2] - это в радианах = [0;90] это в градусах≈ [0;1.57] в числах[π/2;π] =[90;180]≈[1.57;3.14][π;3π/2]=[180;270]≈[3.14; 4.71][3π/2;2π]=[270; 360]≈[4.71;6.28]теперь сравним7π/11 ≈ 7*3,14/11=0,85 это вторая четверть - sin>0-3π/7≈-(3*3,14/7)=-1,35 это четвертая четверть tg<02 -это вторая четверть ctg <0Значит произведение "+"*"-"*"-" = "+"будет положительным
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Вопрос по алгебре:
выясните имеет ли решение система и сколько 3x-2y=7 6x-4y=1
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Ответов: 1
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Вопрос по алгебре:
Укажите значение х,при которых не имеет смысла выражение.
х-1 дробная черта х+1-
Ответов: 3
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Вопрос по английскому языку:
Put each verb in brackets into an appropriate tense:
Ask hundreds of people what they (1)……….(do) on a certain day in August next
year, or the year after, and there (2)………..(be) only one reply. Provided of course that
the people you (3)………..(ask) (4)………..(belong) to the Elvis Presley Fan Club.
Although the King of Rock and Roll (5)………….(die) nearly two decades ago, his fans
(6)……….(meet) every year since then outside his home in Memphis, Tennessee, to
show respect for the singer they (7)………(love) so much. Fans like Jean Thomas, from
Catford in South London. Jean (8) ……….(visit) Gracelands the house where Elvis
(9)………….(suffer) his fatal heart attack, twice in the past five years. ‘The first time I
(10)………….(borrow) the money from my Mum, as I (11)………….(not work) then.
But two years ago I (12)………….(get) married and since then I (13)………….(work) in
my husband Chris’s garage. Chris and I (14) ………….(go) together last year, and we
(15)………(think) of spending two or three months in the USA next year. I
(16)……….(always want) to visit some of the places where Elvis (17)………..(perform).
Like Las Vegas, for example.’ Jean says that Elvis (18)………..(be) her obsession ever
since she (19) ………….(be) ten years old, and she (20)………(own) every single one of his records, good and bad.-
Ответов: 1
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Вопрос по английскому языку:
Переведите на русский язык, обращая внимание на причастия настоящего времени.
1. The girl standing at the window is my sister.
2. Having been sent to the wrong address the letter didn’t rich him.
3. He sat in the arm-chair thinking.
4. She came up to us breathing heavily.
5. The hall was full of laughing people.
6. The singing girl was about fourteen.
7. Having read the book I gave it to Pete.
8. The large building being built in our street is a new school – house.
9. Having finished the experiment the students left the laboratory.
10. Being busy, he postponed his trip.
11. Having been written long ago, the manuscript was impossible to read.
12. Having been built of concrete, the house was always cold in winter.
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Ответов: 1
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