part 1
Những câu hỏi liên quan
Cho góc nhọn ∂ trong tam giác vuông cm :
a) tan∂ = sin∂ trên cos∂
b) cot∂ = cos∂ trên sin∂
c) tan∂ × cot∂ = 1
d) ssin2 ∂ + ccos2∂ =1
e) 1+ ttan2∂ = 1 trên ccos2∂
f) 1 + ccot2∂ = 1 trên ssin2
Gọi cạnh đối là O, cạnh kề là A và cạnh huyền là H.
Ta có: \(\sin\partial=\frac{o}{H}\)
\(\cos\partial=\frac{A}{H}\)
\(\tan\partial=\frac{O}{A}\)
\(\cot\partial=\frac{A}{O}\)
a) \(\Rightarrow\frac{\sin\partial}{\cos\partial}=\frac{\frac{O}{H}}{\frac{A}{H}}=\frac{O}{A}=\tan\partial\)(đpcm)
b) \(\Rightarrow\frac{\cos\partial}{\sin\partial}=\frac{\frac{A}{H}}{\frac{O}{H}}=\frac{A}{O}=\cot\partial\)(đpcm)
c)\(\Rightarrow\tan\partial\times\cot\partial=\frac{O}{A}\times\frac{A}{O}=1\)(đpcm)
d)\(\Rightarrow\sin^2\partial+\cos^2\partial=\left(\frac{O}{H}\right)^2+\left(\frac{A}{H}\right)^2=\frac{O^2+A^2}{H^2}\)
Mà theo định lý Py-ta-go: \(H^2=O^2+A^2\)
\(\Rightarrow\frac{O^2+A^2}{H^2}=1\)\(\Leftrightarrow\sin^2\partial+\cos^2\partial=1\)(đpcm)
e) Ta có:\(1+\tan^2\partial=\)\(1+\left(\frac{O}{A}\right)^2=\frac{O^2+A^2}{A^2}=\frac{H^2}{A^2}\)(theo định lý Py-ta-go)(1)
Mặt khác: \(\frac{1}{\cos^2\partial}=\frac{1}{\frac{A^2}{H^2}}=\frac{H^2}{A^2}\)(2)
Vì (1) = (2) \(\Rightarrow1+\tan^2\partial=\frac{1}{cos^2\partial}\) (đpcm)
f) Ta có: \(1+\cot^2\partial=1+\left(\frac{A}{O}\right)^2=\frac{O^2}{O^2}+\frac{A^2}{O^2}=\frac{O^2+A^2}{O^2}=\frac{H^2}{O^2}\)(theo định lý Py-ta-go)(1)
Mặt khác: \(\frac{1}{\sin^2\partial}=\frac{1}{\frac{O^2}{H^2}}=\frac{H^2}{O^2}\)(2)
Vì (1) = (2) \(\Rightarrow1+\cot^2\partial=\frac{1}{\sin^2\partial}\)(đpcm)
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31 tháng 10 2021 lúc 8:22
1. “I took part in a reality show last year,” said Monica.1 điểmMonica said that I had taken part in a reality show the previous year.Monica said that I had taken part in a reality show last year.Monica said that she had taken part in a reality show the previous year.Monica said that she would take part in a reality show last year.2. “Remember to bring your books,” he said.1 điểmHe said I remembered to bring my booksHe warned me against bringing my books.He asked me if I remembered to bring my b...
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1. “I took part in a reality show last year,” said Monica.
1 điểm
Monica said that I had taken part in a reality show the previous year.
Monica said that I had taken part in a reality show' last year.
Monica said that she had taken part in a reality show the previous year.
Monica said that she would take part in a reality show last year.
2. “Remember to bring your books,” he said.
1 điểm
He said I remembered to bring my books
He warned me against bringing my books.
He asked me if I remembered to bring my books.
He reminded me to bring my books.
3. "You got an A in Chemistry. Congratulations!" Peter said to his classmate
1 điểm
Peter encouraged his classmate to get an A in Chemistry.
Peter congratulated his classmate on getting an A in Chemistry.
Peter persuaded his classmate to get an A in Chemistry.
Peter insisted on getting an A in Chemistry for his classmate.
4. "I'm going to have a job interview tomorrow," said Paul.
1 điểm
Paul said that I am going to have a job interview tomorrow.
Paul said that he was going to have a job interview the following day.
Paul said that I was going to have a job interview the following day.
Paul said that he was going to have a job interview tomorrow
5. "When did you start practising yoga?" asked Tom.
1 điểm
Tom wanted to know when I had started practising yoga.
Tom wanted to know when I was starting to practise yoga.
Tom wanted to know when had I started practising yoga.
Tom wanted to know when did I start practising yoga
6. My father asked me _______ of the film.
1 điểm
what do you think
what did I think
what I thought
What I think
7. My cousin said that he was coming _______.
1 điểm
tomorrow
next day
the day before
the following day
8. He wanted to know whose car I had borrowed______
1 điểm
the previous day
yesterday evening
last night
the last evening
9. She asked me if I _____to see him off at the station.
1 điểm
go
am going
was going
will go
10. I ______Mai for helping me with the housework.
1 điểm
greeted
thanked
congratulated
agreed
11. I warned them _____late-night horror movies.
1 điểm
didn't watch
not watching
don't watch
not to watch
12. John said, “You’d better not lend them any money, Daisy.”
1 điểm
John asked Daisy if she had lent them any money.
John commanded Daisy not to lend them any money.
John advised Daisy not to lend them any money.
John ordered Daisy not to lend them any money.
1. “I took part in a reality show last year,” said Monica.
1 điểm
Monica said that I had taken part in a reality show the previous year.
Monica said that I had taken part in a reality show' last year.
Monica said that she had taken part in a reality show the previous year.
Monica said that she would take part in a reality show last year.
2. “Remember to bring your books,” he said.
1 điểm
He said I remembered to bring my books
He warned me against bringing my books.
He asked me if I remembered to bring my books.
He reminded me to bring my books.
3. "You got an A in Chemistry. Congratulations!" Peter said to his classmate
1 điểm
Peter encouraged his classmate to get an A in Chemistry.
Peter congratulated his classmate on getting an A in Chemistry.
Peter persuaded his classmate to get an A in Chemistry.
Peter insisted on getting an A in Chemistry for his classmate.
4. "I'm going to have a job interview tomorrow," said Paul.
1 điểm
Paul said that I am going to have a job interview tomorrow.
Paul said that he was going to have a job interview the following day.
Paul said that I was going to have a job interview the following day.
Paul said that he was going to have a job interview tomorrow
5. "When did you start practising yoga?" asked Tom.
1 điểm
Tom wanted to know when I had started practising yoga.
Tom wanted to know when I was starting to practise yoga.
Tom wanted to know when had I started practising yoga.
Tom wanted to know when did I start practising yoga
6. My father asked me _______ of the film.
1 điểm
what do you think
what did I think
what I thought
What I think
7. My cousin said that he was coming _______.
1 điểm
tomorrow
next day
the day before
the following day
8. He wanted to know whose car I had borrowed______
1 điểm
the previous day
yesterday evening
last night
the last evening
9. She asked me if I _____to see him off at the station.
1 điểm
go
am going
was going
will go
10. I ______Mai for helping me with the housework.
1 điểm
greeted
thanked
congratulated
agreed
11. I warned them _____late-night horror movies.
1 điểm
didn't watch
not watching
don't watch
not to watch
12. John said, “You’d better not lend them any money, Daisy.”
1 điểm
John asked Daisy if she had lent them any money.
John commanded Daisy not to lend them any money.
John advised Daisy not to lend them any money.
John ordered Daisy not to lend them any money.
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27 tháng 11 2021 lúc 13:15
1. Find the word whose underlined part differs from the other three in pronunciation: *1 điểmABCD2. Find the word whose underlined part differs from the other three in pronunciation: *1 điểmABCD3. Find the word whose underlined part differs from the other three in pronunciation: *1 điểmABCD4. Find the word whose underlined part differs from the other three in pronunciation: *1 điểmABCD
Đọc tiếp
1. Find the word whose underlined part differs from the other three in pronunciation: *
1 điểm
A
B
C
D
2. Find the word whose underlined part differs from the other three in pronunciation: *
1 điểm
A
B
C
D
3. Find the word whose underlined part differs from the other three in pronunciation: *
1 điểm
A
B
C
D
4. Find the word whose underlined part differs from the other three in pronunciation: *
1 điểm
A
B
C
D
Divide $285 into three parts such that the second part is 1/4 of the third part and the ratio between the first and the second part is 4:3 The first part is
Divide $285 into three parts such that the second part is 1/4 of the third part and the ratio between the first and the second part is 4:3 The first part is
11 tháng 9 2021 lúc 15:02
*Choose the word or phrase with the same meaning as the underlined part.1. Unselfishness is the very essence of friendship.A. romantic part B. important part C. difficult part D. interesting part2. Fortunately, our work was finished as scheduled.A. completed B. held C. presented D. ended3. We spent an enjoyable evening boating in the river.A. pleasant B. boring C. comfortable D. free4. Math and English are compulsory subjects on this course.A. effective B. required C. separated D. difficult5. Th...
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*Choose the word or phrase with the same meaning as the underlined part.
1. Unselfishness is the very essence of friendship.
A. romantic part B. important part C. difficult part D. interesting part
2. Fortunately, our work was finished as scheduled.
A. completed B. held C. presented D. ended
3. We spent an enjoyable evening boating in the river.
A. pleasant B. boring C. comfortable D. free
4. Math and English are compulsory subjects on this course.
A. effective B. required C. separated D. difficult
5. The role of scientists is to observe and describe the world.
A. obey B. determine C. watch D. keep
6. Each nation has many people who voluntarily take care of others.
A. look after B. take part in C. organize D. clean up
*Choose the word or phrase with the same meaning as the underlined part.
essence of friendship.
finished as scheduled.
enjoyable evening boating in the river.
compulsory subjects on this course.
observe and describe the world.
take care of others.
A. look after B. take part in C. organize D. clean up
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Choose the words whose underlined part is pronounced differently 1.brothers 2.letters 3.hats Choose the words whose underlined part is pronounced differently 1.chairs 2.books 3.pictures Choose the words whose underlined part is pronounced differently 1.parents 2.fathers 3.sisters Giúp mình với ạ (Âm s nhé Mn)
Choose the words whose underlined part is pronounced differently
1.brothers 2.letters 3.hats
Choose the words whose underlined part is pronounced differently
1.chairs 2.books 3.pictures
Choose the words whose underlined part is pronounced differently
1.parents 2.fathers 3.sisters
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3.hats
2.books
1.parents
(mình thấy mấy câu này đều có 2 từ đã là âm r cuối rồi mà..)
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Find the word which has a different sound in the part underlined.(1 Point)gathermonthlyfatherbrother2.Find the word which has a different sound in the part underlined.(1 Point)foldcloseclothhold3.Find the word which has a different sound in the part underlined.(1 Point)testdressC. thesethen4.Find the word which has a different sound in the part underlined.(1 Point)manwomanrelaxbadminton5.Find the word which has a different sound in the part underlined.(1 Point)mountainmouseroundcousin6.Find the...
Đọc tiếp
Find the word which has a different sound in the part underlined.
(1 Point)
gather
monthly
father
brother
2.Find the word which has a different sound in the part underlined.
(1 Point)
fold
close
cloth
hold
3.Find the word which has a different sound in the part underlined.
(1 Point)
test
dress
C. these
then
4.Find the word which has a different sound in the part underlined.
(1 Point)
man
woman
relax
badminton
5.Find the word which has a different sound in the part underlined.
(1 Point)
mountain
mouse
round
cousin
6.Find the odd word in each line.
(1 Point)
walk
borrow
took
cook
7.Find the odd word in each line.
(1 Point)
went
got
eat
drank
8.Find the odd word in each line.
(1 Point)
running
driving
skipping
swimming
9.Find the odd word in each line.
(1 Point)
book
show
comedy
cartoon
10.Find the odd word in each line.
(1 Point)
boring
educational
interesting
funny
11.Choose the correct answer A, B or C.
There ___ an interesting match on TV last night.
(1 Point)
is
were
was
12.Choose the correct answer A, B or C.
My dad ___ a lot of tennis some years ago.
(1 Point)
plays
played
is playing
13.Choose the correct answer A, B or C.
I was at the gym last Sunday, but I ___ you there.
(1 Point)
not saw
don't see
didn't see
Find the word which has a different sound in the part underlined.
(1 Point)
gather
monthly
father
brother
2.Find the word which has a different sound in the part underlined.
(1 Point)
fold
close
cloth
hold
3.Find the word which has a different sound in the part underlined.
(1 Point)
test
dress
C. these
then
4.Find the word which has a different sound in the part underlined.
(1 Point)
man
woman
relax
badminton
5.Find the word which has a different sound in the part underlined.
(1 Point)
mountain
mouse
round
cousin
6.Find the odd word in each line.
(1 Point)
walk
borrow
took
cook
7.Find the odd word in each line.
(1 Point)
went
got
eat
drank
8.Find the odd word in each line.
(1 Point)
running
driving
skipping
swimming
9.Find the odd word in each line.
(1 Point)
book
show
comedy
cartoon
10.Find the odd word in each line.
(1 Point)
boring
educational
interesting
funny
11.Choose the correct answer A, B or C.
There ___ an interesting match on TV last night.
(1 Point)
is
were
was
12.Choose the correct answer A, B or C.
My dad ___ a lot of tennis some years ago.
(1 Point)
plays
played
is playing
13.Choose the correct answer A, B or C.
I was at the gym last Sunday, but I ___ you there.
(1 Point)
not saw
don't see
didn't see
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SGK Friends Global - Trang 100
21 tháng 11 2023 lúc 21:18
Read part 2 of the article. Why is Apollo 13 mission described as a successful failure? Rewrite the underlined clauses in part 2 as participle clauses.1 ... fitted with its own oxygen tank...PART 2The astronauts left the main part of the spaceship and went inside the lunar module, 1which had been fitted with its own oxygen tank. But inside the smaller module, 2which was designed to hold only two people, carbon dioxide levels started rising. The astronauts, 3 who had been following instructions f...
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Read part 2 of the article. Why is Apollo 13 mission described as a 'successful failure'? Rewrite the underlined clauses in part 2 as participle clauses.
1 ... fitted with its own oxygen tank...
PART 2
The astronauts left the main part of the spaceship and went inside the lunar module, 1which had been fitted with its own oxygen tank. But inside the smaller module, 2which was designed to hold only two people, carbon dioxide levels started rising. The astronauts, 3 who had been following instructions from the ground crew, made special filters out of plastic bags and cardboard. Then they waited in the cold and dark while the ground crew, 4 who were working 24 hours a day, tried to work out a way to bring them home. If some people in America were losing interest in the Space Program, the Apollo 13 crisis, 5 which was discussed on all the TV news programmes, changed all that. The astronauts 6 who were risking their lives and the people 7 who were trying to save them all became national heroes - especially when Apollo 13 returned safely to Earth with all three astronauts alive.
2 which was designed to hold only two people
=> designed to hold only two people
(được thiết kế để chỉ chứa hai người)
3 who had been following instructions from the ground crew
=> following instructions from the ground crew
(làm theo hướng dẫn của nhân viên mặt đất)
4 who were working 24 hours a day
=> working 24 hours a day
(làm việc 24 giờ một ngày)
5 which was discussed on all the TV news programmes
=> discussed on all the TV news programmes
(được thảo luận trên tất cả các chương trình tin tức truyền hình)
6 who were risking their lives
=> risking their lives
(mạo hiểm tính mạng của họ)
7 who were trying to save them
=> trying to save them
(cố gắng cứu họ)
The Apollo 13 mission is often described as a 'successful failure' because while the mission did not achieve its primary goal of landing on the moon, the mission became a triumph of human ingenuity and teamwork in the face of crisis. Despite the explosion that damaged the spacecraft and the many challenges faced by the crew and the ground crew during the mission, all three astronauts returned safely to Earth, thanks to the remarkable efforts of everyone involved.
(Sứ mệnh Apollo 13 thường được mô tả là một "thất bại thành công" bởi vì mặc dù sứ mệnh không đạt được mục tiêu chính là hạ cánh trên mặt trăng, nhưng sứ mệnh này đã trở thành một chiến thắng của sự khéo léo của con người và tinh thần đồng đội khi đối mặt với khủng hoảng. Bất chấp vụ nổ làm hỏng tàu vũ trụ và nhiều thách thức mà phi hành đoàn và nhân viên mặt đất phải đối mặt trong nhiệm vụ, cả ba phi hành gia đã trở về Trái đất an toàn nhờ những nỗ lực đáng kể của mọi người tham gia.)
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Part 3: Read the following sentences about the different forms of energy available. Match the sentences in Part One with correct sentences in Part Two. (10 points)PART ONE0. Muscles and wood were the first sources of energy used by early man.1. Coal made the Industrial Revolution in the nineteenth century possible.2. Today we depend on oil more than any other fuels.3. Gas is considered as a “mineral” because, together with coal, it is part of the earth’s crust.4. Hydroelectric power is used to...
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Part 3: Read the following sentences about the different forms of energy available. Match the sentences in Part One with correct sentences in Part Two. (10 points)
PART ONE
0. Muscles and wood were the first sources of energy used by early man.
1. Coal made the Industrial Revolution in the nineteenth century possible.
2. Today we depend on oil more than any other fuels.
3. Gas is considered as a “mineral” because, together with coal, it is part of the earth’s crust.
4. Hydroelectric power is used to produce electricity.
5. Geothermal energy is produced from the heat stored in the earth’s core.
6. The wind was used as a power source over 1,300 years ago in Persia when the first windmill was built to return a millstone.
7. Waves have enormous power.
8. Incoming tides can be trapped behind a dam across a bay or an estuary.
9. A huge amount of solar energy reaches the earth’s outer atmosphere.
10. Nuclear fuels, such as uranium-235 and plutonium, can be made to produce immense heat by a process called “fission”.
PART TWO
Like oil, it is a fossil fuel and is thus a non-renewable source of energy.
One danger, however, is in getting rid of the radioactive wastes which are produced.
They increase and decrease more slowly than the wind, thus making them easier to use as a source of energy.
It was the first fossil fuel to be used to power machinery.
However, it is thinly spread, and collecting it in countries like Britain and northern Europe is still difficult and expensive.
It is used as a fuel in cars, ships and aeroplanes, and even in rockets.
It is produced by the fall of water trapped in a dam.
It took thousands of years to progress to using coal on a large scale.
This internal heat helps to produce geysers and steam springs and can be used to generate eletricity in countries like New Zealand.
The water is then allowed to flow out past water wheels as the tide goes out.
For morden purposes, however, it is necessary to build a machine which can store the energy obtained for use on calm days.
Example: 0 – H
1........ 2. ....... 3......... 4......... 5........
6…… 7……. 8….… 9……. 10…..