Chứng minh các đẳng thức sau:
a.\(\frac{1+sin^2x}{1-sin^{2^{ }}x}=1+2tan^2x\)
b.\(\frac{sin^3a-cos^3a}{sina-cosa}-sina.cosa=1\)
c.\(\frac{1+cosx+cos2x+cos3x}{2cos^2x+cosx-1}=2cosx\)
e.\(\frac{1-2sin^2a}{cosa+sina}+\frac{2cos^2a-1}{cosa-sina}=2cosa\)
d.\(\frac{1-cosx+cos2x}{sin2x-sinx}=cotx\)
MỌI NGƯỜI GIÚP MÌNH VỚI .MÌNH CẢM ƠN RẤT NHIỀU
1: To-Verb/ Verb/ V-ing: Rewrite the sentences without changing the meaning
1.Shall we organize the party?
-What about ......
2.Why don't we phone him?
-I suggest .........
3.I am very pleased that we shall go fishing next weekend.
-I am looking .........
4.I expect that she will give me some advice.
-I expect her ......
5.Taking some medicine is good for you now.
-It's good .......
6.It takes us 20 minutes to cycle from home to school.
-We spend ......
7.How about getting together next Sunday.
-Let's ....
8.She isn't allowed to go out at night by her parents.
-Her parents don't .......
9. Shall we invite our friends to the party on Sunday?
-Do you consider .........
10. My younger sister doesn't often get up early in the morning.
-My younger sister isn't .........
Exercise 2: COMPARISIONS: Rewrite the sentences without changing the meaning
1. This house is the highest in the city.
=> No house ........
2. The black dress is more expensive than the white one.
=> The white dress
3. According to me, English is easier than Maths.
=> According to me, Maths ....
4. Mary is the most intelligent students in my group
=> No one
5.This is the first time I have ever met such a pretty girl.
=> I have never .....
7. Peter speaks English better than Tom.
->Tom .....
8. No cars in the world are more expensive than Japanese ones.
=> Japanese cars...
9. Other oceans in the world aren't as large as the Pacific one.
=> The Pacific Ocean ....
10. I've never met any more dependable person than George.
=> George........
MỌI NGƯỜI GIÚP MÌNH VỚI MÌNH CẢM ƠN NHIỀU NHIỀU
Exercise 2. Choose the word which has a different stress pattern from that of the others
1. A. traditional B. engagement C. proposal D. ancestor
2. A. status B. argue C. basic D. against
3. A. village B. banyan C. bamboo D. entrance
4. A. national B. newspaper C. dormitory D. biology
5. A. economic B. experience C. invitation D.introduction
6. A. contaminate B. environment C. psychology D. inorganic
7. A. pesticides B. fertilizers C. detergents D. chemical
8. A. consumption B. sustainable C. alternative D. biological
9. A. endangered B. limited C. awareness D. renewable
10. A. disappear B. environment C. contaminate D. renewable
11. A. evaporate B. disaster C. poisonous D. Diversity
12. A. mature B. affect C. challenge D. employ
MỌI NGƯỜI LÀM GIÚP MÌNH VỚI MÌNH CẢM ƠN
Exercise 1. Choose the word whose underlined part is pronounced differently from the others.
1. A. misses B. catches C. faces D. hates
2. A. advises B. raises C. devises D. goes
3. A. surfaces B. temples C. exercises D. pages
4. A. names B. lives C. dances D. tables
5. A. girls B. works C. degrees D. opportunities
6. A. moves B. bosses C. brushes D. foxes
7. A cleaned B. brushed C. played D. snowed
8. A. eliminated B. forced C. worked D. missed
9. A. finished B. played C. influenced D. helped
10A. explored B. named C. travelled D. separated
11. A. laughed B. washed C. decided D. watched
12. A. worked B. laughed C. hoped D. naked
MỌI NGƯỜI LÀM GIÚP MÌNH VỚI MÌNH CẢM ƠN
RELATIVE CLAUSES: Use Who/whom/which/ that/ whose/ where/ when or why to combine these sentences.
1. The man is a lawyer. My parents bought his house.
2. Can you understand the question? She has asked you the question three times.
3. The street is very nice. It leads to my school.
4. The doctor isn't here today. You spoke to him yesterday.
6. This is Mr Smith. His son plays in our team.
7. Romeo and Juliet were lovers. Their parents hated each other.
8. My brother wants to meet you. You talked to him at my birthday party.
9. Do you remember this present? You gave it to me when I graduated from university.
10. I would like to come back to my high school. I had studied in that school for 5 years.
12. They're the people. Their shop burned down last week.
13. This is Mrs. Jones. Her son won the championship last year.
14. The winner, Ross Rebagliati, lives in Whistler, BC. Many young snowboarders admire him.
15. John didn't study for the exam. That was a very stupid thing to do.
16. I like the town. You live there.
17. My parents send their best wishes. You met them last month.
18. Their parents are anxious about their children. The children come back late
19. The architect designed these flats. He has moved to HCM City.
20. The boy gave his parents big hugs before he left. He went abroad to study.
MỌI NGƯỜI ƠI GIÚP MÌNH VỚI MÌNH CẢM ƠN
Một bình có chứa khí hidro nên V=10 lít,áp suất p=50at,nhiệt độ 7 độC. Khi nung nóng bình, do bình hở nên có một phần khí thoát ra; phần khí còn lại có nhiệt độ 17 độ C và vẫn dưới áp suất như cũ. Tính khối lượng khí Hidro đã thoát ra ngoài.
MOỊ NGƯỜI GIÚP MÌNH NHANH NHANH VỚI MÌNH CẢM ƠN NHIỀU