Cho nửa đường tròn tâm O, bán kính R, đường kính AB. Gọi C,D là 2 điểm thuộc nửa đường tròn. Các tia AC, AD cắt tia tiếp tuyến Bx lần lượt tại E và F (F nằm giữa B,E).
a) EB^2= EC . EA
b) Tứ giác CDEF nội tiếp được 1 trong đường tròn.
c) Tính phần S nửa hình tròn (O;R) nằm bên ngoài tứ giác ACDB theo R trong trường hợp góc COD = 30 độ, góc DOB = 60 độ.
I. Fill in each gap with a word from the box.
Course fee desposit Native Experiences intermediate editions advance published. Scenery
1. She collects first .... of Victorian novels.
2. Everyone ..... these problems at some time in their lives.
3. It's cheaper if you book the tickets in ........
4. They stopped at the top of the hill to admire the ......
5. There is not entrance ...... to to the gallery.
6. This novel is too difficult for ......... students of English.
7. Tim did a three-years ....... in Linguistics at Newcastle .
8. To open an account, you need to make a minimum ....... of $500.
9. The report will be ...... on the Internet.
10. Sir Lanka is her ....... country, but she's been living in Belgium for the past five years.
II. Put the following sentences in the correct order to make a complete dialogue. Start like this:
1. Our English is still poor. Let's attend an English evening class this summer vacation.
2. No, it isn't. It's right in the center of HCM city.
3. We should attend a local center. The tuition is not expensive.
4. That's a good idea. But where should we learn?
5. How much is the tution?
6. Is it far from here?
7. Yes, let go now.
8. I'm not sure. It depends on how long our course lasts. I think we should go there and see.
9. Why don't we study at the Vietnam USA Societ (VUS)?
10. I don't think so because we can't learn with native teachers.
Your answer : 1-4-