1)cho sinx=1/2, π/2<x<π. tính sin2x,cos2x,sinx/2,cosx/2 b) cho sin2x=-4/5,π/2<x<3π/4 Tính cos2x,sinx,cosx

Giúp mik vs ạ Mik cần gấp thanks mn

Cho đường tròn ( O; R ) và hai đường kính AB, CD vuông góc với nhau. Trên đoạn OC lấy điểm N bất kì, đường thẳng AN cắt đường tròn ở M a) Chứng minh tứ giác NMBO nội tiếp. Xác định tâm I và bán kính của đường tròn ngoại tiếp tứ giác NMBO b) Hai đường thẳng CD và MB cắt nhau ở E. Chứng minh MC là tia phân giác của góc NME c) Chứng minh AM.DN = AC. DM d) Chứng minh ON.OE không đổi khi N di chuyển trên OC e) Nếu N là trung điểm của OC. Tính AM theo R, diện tích hình quạt MOB

các sự kiện chính trong phong trào giải phóng dân tộc ở các nước á, phi, mỹ la tinh

Một khu vườn có chu vi 140m. Người ta làm một lối đi chung xung quanh vườn có chiều rộng lối đi là 1m và diện tích vườn còn lại là 1064m^2. Tính chiều dài và chiều rộng của khu vườn. giải theo cách lập phương trình hộ mik nhé

Dùng so sánh nhất và so sánh hơn để điền vào chỗ trống: 1. My new house in the city is (big) ……………………..than yours. 2. This flower is (beautiful) ……………………………..than that one. 3. This is the (interesting) ………………………book I have ever read. 4. Non-smokers usually live (long) ……………………………..than smokers. 5. Which is the (dangerous) ……………………………..animal in the world? 6. A holiday by the sea is (good) …………………….than a holiday in the mountains. 7. It is strange but often a coke is (expensive) ……………………….than a beer. 8. Who is the (rich) ……………………….woman on the earth these days? 9. The weather this summer is even (bad) ………………………than last summer. 10. He was the (clever) ………………………………….thief of all. Tìm lỗi sai trong mỗi câu sau (A, B, C hoặc D) 1. I spend three days to visit Ha Long bay. A B C D 2. Loan is my parents' daughter, so she is my brother A B C D 3. Would you like to going to the movies with us tonight? A B C D 4. There is a few water in the bottle. A B C D 5. The store is between we house and the movie theater. A B C D 6. This is my new pen and that is their pens. A B C D 7. Last summer my parents buyed me a lot of different gifts. A B C D 8. There are five bookshelf in my sister’s bedroom. A B C D Chuyển các câu sau thành bị động: 1. People used oil-lamps years ago. - Oil-lamps ………………………………………………. 2. The boss will meet him tomorrow in the restaurant. - He ……………………………………………………… 3. The old woman feeds fowls twice a day. - The fowls ……………………………………………… 4. Does he often clean the windows? - Are……………………………………………………….? 5. She doesn't grow any trees in her garden. - Trees …………………………………………………….. 6. The company will give him some money when he retires - When he retires, he …………………………………… 7. They took it back to the zoo. - It …………………………………………………………… 8. Someone picks the fruits everyday. - Fruits……………………………………………………….. 9. Does the girl do the housework? - Is …………………………………………………………..? 10. They don't drive out the cattle to the field in the winter. - The cattle………………………………………………… 11. The club bought him 2 years ago for a fee of $20 000. - He ………………………………………………………….. 12. I’ll meet her at the airport. - She ………………………………………………………… 13. Japan makes a lot of cars. - Cars………………………………………………………… 14. They don't keep cows over there. - Cows ……………………………………………………… 15. Does machine do most of the farm work? - Is …………………………………………………………?

cho 2 số a và b thoả mãn a<b. Cm 2021-2021a>2019-2021b

1. Tại sao ngta nói nếu ko có thực vật thì cx ko có loài ng? 2. Hút thuốc lá và thuốc phiện có hại ntn?

helpppppppppppp meeeeeeeeeeeeeeee

Đặt câu hỏi cho các từ gạch chân: 1. They are planting the trees in the garden. ->................................................................................ 2. She will visit Hanoi next week. ->........................................................................... .... 3. She often watches TV at 6. 45 p.m in the evening. ->................................................................................. 4. We will travel to the moon by a super car. ->.................................................................................... 5. Tom and Mai are reading a book. -> ............................................................................... 6. All the buildings in London are old. -> ............................................................................... 7. It is very cold in Sweden in the winter. ->............................................................................... 8. My father was in Ha Noi last month. ->................................................................................ 9. She went to the doctor because she was sick. -> ................................................................................ 10. Nam left home at 7 o'clock yesterday. ->................................................................................ 11. My future house will be on the ocean. ->................................................................................. 12. She goes to the fitness center three times a week. ->................................................................................. 13. They joined the environment project last Sunday. ->................................................................................. 14. Our class has Geography on Monday. ->.................................................................................... Viết lại câu với nghĩa không đổi: 1. My house is bigger than your house. => Your house …………………………………………………………………………………… 2. The black car is cheaper than the red one => The red car……………………………………………………………………………………. 3. There is a sink, a tub and a shower in the bathroom. => The bathroom ………………………………………………………………………………… 4. No one in the group is taller than Trung. => Trung …………………………………………………………………………………………. 5. Do you have a better refrigerator than this? => Is this………………………………………………………………………………………….. 6. My house is the oldest one on the street. => No houses ………………………………………………………………………………….…. 7. My house has a living room, a bed room and a kitchen. => There is …………………………………………………………………………………….…. 8. No one can sing more beautifully than Madonna. => Madonna ………………………………………………………………………………………. 9. Why don’t we go to the beach for a change? => How about ………………………………………………………………………………….…. 10. They live at 83 Son Tay Street. => Their…………………………………………………………………………………………… Viết lại câu với nghĩa không đổi: 1. The Nile is the longest river in the world. -No river................................................................................................................... 2. We will probably visit Japan in the future. - We might................................................................................................................ 3. My brother can run very fast. -My brother is........................................................................................................... 4. Rose likes badminton best. - Rose’s favourite....................................................................................................... 5. My children like studying English very much - My children are.......................................................................................................