Chứng minh rằng mọi n thuộc z: a) n (2n - 3) - 2n (n + 2) luôn chia hết cho 7 b) (n - 1) (n + 1) - (n - 7) (n - 5) chia hết cho 12

bày tỏ quan điểm của bản thân về lòng biết ơn đối với cha mẹ qua bài câu chuyện quả táo

Các bạn giúp mình với mình cảm ơn ạ

Cho hình thang ABCD có ∠B= ∠C=90 độ. Các đường chéo vuông góc với nhau tại Q. a) C/m $\frac{1}{AB^{2}}$ -$\frac{1}{CD^{2}}$=$\frac{1}{QB^{2}}$-$\frac{1}{QC^{2}}$ b) Các đường trung tuyến QE và BF của Δ BQC vuông góc với nhau tại G, biết BQ= $\sqrt[2]{6}$ cm. Tính BC.

80:81,25=? giải giúp mik thx nha

cho hình thang ABCD(AB song song CD). Gọi M là trung điểm của AD ,N là trung điểm của BC. Qua M kẻ đường thẳng song song với AB cắt AC tại K. CMR AK=CK và MNK thẳng hàng

TEST 1 I. Choose the word that has the underlined part pronounced differently from the others. 1. a. pan b. match c. lamp d. save 2. a. cover b. folder c. send d. answer 3. a. injure b. knife c. kill d. sink 4. a. steamer b. reach c. breakfast d. bead 5. a. reach b. such c. chemical d. chore II. Choose the word or phrase that best completes each unfinished sentence below or substitutes for the underlined word or phrase. 6. She felt and hurt_______ . a. her b. herself c. himself d. myself 7. They bought ______ a new car. a. theyseif b. theyselves c. themselves d. themself 8. They _____ talk in the library. a. mustn’t b. don’t have to c. shouldn’t to d. needn’t to 9. He ______ wear a suit to work but he usually does. a. doesn’t have to b. mustn’t c. have to d. must 10. _____ not ask Kate to go with you? a. When b. Why c. What d. Who 11. I asked Sara ______ me to the station. a. drive b. drives c. to drive d. driving 12. Her parents won’t let her_______ with her friends. a. go out b. goes out c. to go out d. going out 13. It takes a long time ______ a language. a. learn b. to learn c. learning d. learns 14. From the tower, they looked down on the city________ . a. above b. beneath c. over d. next 15. Our lives depend on _____ . a. electric b. electricity c. electrically d. electrical III. Choose the word (a, b, c, or d) that best fits each of the blank spaces. I’m a student (21) _____ Bristol University. I share a house with three other students. It’s quite a (22) _____ house. We all have our own (23)_____ There (24) _______ a bed, a desk, a chair, and a wardrobe in the room. It has a washbasin and a mirror in the corner, too. We all share the kitchen, the living room, and the bathroom. We sometimes have arguments about things, like when someone spends too long (25)______ the bathroom, but we have a lot of fun, (26)_______ . 21. a. in b. at c. on d. inside 22. a. tall b. big c. heavy d. old 23. a. rooms b. flats c. houses d. apartments 24. a. has b. have c. is d. are 25. a. on b. in c. at d. over 26. a. too b. either c. neither d. a & b IV. Read the following passage and choose the item (a, b, c, or d) that best answers each of the questions about it. I live in a house near the sea. It’s an old house, about 100 years old, and it’s very small. There are two bedrooms upstairs but no bathroom. The bathroom is downstairs next to the kitchen and there’s a living room where there is a lovely old fireplace. There’s a garden in front of the house. The garden goes down to the beach and in spring and summer there are flowers everywhere. So, I have a lot of visitors. My city friends often stay with me. I love my house for many reasons: the garden, the flowers in summer, the fire in winter, but the best thing is the view from my bedroom window. 27. Where does the author live? a. near the sea b. in the country c. in the city d. a & b 28. How many rooms are there in his/ her house? a. two b. three c. four d. five 29. There’s a garden _____ the house. a. before b. behind c. beside d. beneath 30. The author loves the house because of _____ a. the garden b. the flowers in summer c. the fire in winter d. all are correct 31. What does the author like best? a. the lovely old fireplace b. the garden c. the flowers in spring and summer d. the viewfrom his/ her bedroom window

I. Rewrite the sentences, beginning with the words in parentheses 1. She has plenty of money, but she is very mean. (although) => 2. They have a car, but they rarely use it. (though) => 3. He was innocent, but he was sent to prison. (although) => 4. He has a number of relatives living nearby, but he never visits them (even though) => 5. She never takes any kind of exercise, but she is quite fit and healthy. (even though) => 6.The keyboard wasn’t working well. She tried to finish the letter (although) => 7.The forecast said it would rain. It turned out to be a beautiful day. (although) => 8.I’m no better. I’ve taken the bill. (even though) => 9. The traffic was bad. I arrived at the airport on time. (though) => 10. I didn’t get the job. I had all necessary qualifications. (though) => 11. We enjoyed the vacation. It rained a lot. (although) => 12. She felt sick. She went to work. (though) => 13. I was really tired. I couldn’t sleep. (even though) => 14. He is very rich. He isn’t happy. (although) => 15. She couldn’t answer the question. She is very intelligent. (though) => 16. He tried. He was not successful. (though) => 17. His life is hard. He determined to study well. (although) => 18. He was wise and experienced. He was not taken in. (though) => II.Rewrite the sentences with the word given. 1. Although he has a very important job, he isn’t particularly well-paid. =>In spite of 2. Although I had never seen her before, I recognized her from a photograph. => Despite 3. She wasn’t wearing the coat although it was quite cold. =>In spite of 4. We thought we’d better invite them to the party although we don’t like them very much. => Despite 5. Although I didn’t speak the language, I managed to make myself understand. =>In spite of 6. Although the heat was on, the room wasn’t warm. => Despite 7. I didn’t recognize her although I’d met her twice before. =>In spite of 8. We’re not very good friends although we’ve known each other a long time. => Despite 9. Although Minh was ill, he still came to the meeting. =>In spite of 10. Although he promised that he wouldn’t be late, he didn’t arrive until 9 o’clock. => Despite

Giải giúp mình với. Ghi rõ ra, đừng làm tắt nha! Mình cần gấp ạ!

Giải giúp mình vs ạ mình cần gấp,mình cảm ơn