Phương trình sinx=2/3 có bao nhiêu nghiệm thuộc (-π; π) ? A. 1 B. 2 C. 3 D. 4

Exercise 3: Choose the best answer to rewrite the original one. 1. "You have not done your work well," said the teacher to me. A. The teacher told me I hadn't done my work well. B. The teacher told me I haven't done my work well. C. The teacher told me I hadn't done your work well. D. The teacher told me I hadn't done his work well. 2. "This man spoke to me on the road," said the woman. A. The woman said that man had spoken to me on the road. B. The woman said that man has spoken to her on the road. C. The woman said that man spoke to her on the road. D. The woman said that man had spoken to her on the road. 3. "I can't explain this rule to you," said my classmate to me. A. My classmate told me he/she can't explain that rule to me. B. My classmate told me he/she couldn't explain that rule to me. C. My classmate told me he/she couldn't explain that rule to you. D. My classmate said me he/she couldn't explain that rule to me. 4. The teacher said to class, "We shall discuss this subject tomorrow." A. The teacher told the class they would discuss that subject the next day. B. The teacher told the class they will discuss that subject the next day. C. The teacher said the class they would discuss that subject the next day. D. The teacher told the class they discussed that subject the next day. 5. The woman said to her son, "I am glad I am here." A. The woman told her son I was glad she was there. B. The woman told her son she was glad I was there. C. The woman told her son she was glad she was there. D. The woman told to her son she was glad she was there. 6. Mike said, "We have bought these books today." A. Mike said they bought those books that day. B. Mike said they had bought those books that day. C. Mike said they have bought those books that day. D. Mike said they had bought those books today. 7. Sarah said, "I read Jane Eyre last year." A. Sarah said she had read Jane Eyre the previous year. B. Sarah said she read Jane Eyre the previous year. C. Sarah said she has read Jane Eyre the previous year. D. Sarah said she would read Jane Eyre the previous year. 8. Tony said, "I have never been to London, I think I shall go there next year." A. Tony said he has never been to London and he thinks he would go there the following year. B. Tony said he had never been to London and he thought he would go there the following year. C. Tony said he had never been to London and he thinks he will go there the following year. D. Tony said he would have never been to London and he thought he would go there the following year. 9. Barbara said, "I saw them at my parents' house last year." A. Barbara said I had seen them at my parents' house the previous year. B. Barbara said she saw them at her parents' house the previous year. C. Barbara said she had seen them at her parents' house the previous year. D. Barbara said they had seen her at her parents' house the previous year. 10. He said, "I haven't seen my cousin today." A. He said he hasn't seen his cousin that day. B. He said he hadn't seen my cousin that day. C. He said he hadn't seen his cousin that day. D. He said I hadn't seen his cousin that day.

1.Rút gọn a) (2x-3)(x-1)-(x-2)^2-(x-1)(x+1) b)(3x-1)(x+2)- 2(x+3)^2-(x-2)(x-3)

giúp mk vs Câu 3: Cho 2 đường thẳng m và n song song. Đường thẳng d cắt m và tạo vs đường thẳng góc m bằng 30 độ. Góc tạo bởi đường thẳng d và đường thẳng n là bao nhiêu độ. Vẽ hình

Phân tích đa thức sau thành nhân tử (x-y)^3+(y+z)^3-(z+x)^3

Chời má tên tui đứng trước người may mắn đầu tiên Calli chữ Xuiii

Giúp e vs bài này khó quá e hok bik làm. E cảm ơn

giúp mình giải bài này với mn ạ

a, Sự co dãn của ruột có tác dụng như thế nào trong quá trình tiêu hóa? b, Với một khẩu phần ăn có đầy đủ các chất, hãy cho biết những loại chất nào trong thức ăn cần được tiêu hóa hóa học tiếp sau sự tiêu hóa ở khoang miệng và sau sự tiêu hóa ở dạ dày?

một người đi từ A →B.Trong 2/3 quãng đường đầu người đó đi với vận tốc 20km/h,quãng đường còn lại người đó đi với vận tốc 30km/h .Hỏi trên lí thuyết người đó đi với vận tốc trung bình bao nhiêu km/h (biết thời gian trong lí thuyết =thời gian thực tế ngườ đó đi) help me i give 5 sao