tính hệ số \(x^2\)trong khai triển biểu thức \(\left(x+\dfrac{2}{x}\right)^{10}\)

1) \(\sqrt{2x^2+4x-1}>x+1\)

2)\(\sqrt{4x^2+101x+64}>2\left(x+10\right)\)

3)\(\sqrt{x^2-5x-14}>x-3\)

1 ô tô chuyển động từ trạng thái nghỉ trên 1 đường thẳng sau t giây đạt vận tốc được là V, nếu vận tốc đạt được 1 lần nữa thì lực tác dụng bao nhiêu

Cho tam giác ABC với A(2; 5), B(1; 1), C(3; 3). Tìm tọa độ điểm D để ABCD là hình bình hành. Tìm tọa độ tâm hình bình hành đó

Một phân tử mARN có tỉ lệ các loại nu A:U:G:X= 1:2:3:4. gen tổng hợp phân tử mARN nói trên chứa 4050 liên kết hirdro
a) Xác định số nu mỗi loại của gen
b) Xác định số ribonu mỗi loại của phân tử mARN nói trên?

II. Complete the sentences with"used to" or "be used to"

1. Jane(work).................... for the telephone company, but now she has a job at the post office

2. Did work doesn't brother me. I(work)................................ hard. I've worked hard all my life

3. Dick(have)............................. mustache. but he doesn't any more. He shaved it off because his wife didn't like it. I (see, not)....................... him without his mustache. He still looks strange to me

4. When I was a child, I (think)...................................anyone over 40 was old. Of course, now that I'm middle- aged, I agree with those who say"Life begins at 40"

5. It(take)............................................ weeks or months to cross the Atlantic Ocean from Europe to American , but now it takes only a matter of hours

6. Even though Jason is only 12, he(fly)................................. on airplane. His father is pilot and has taken Johnson with him in a plane many times

7. Michale(take)....................................... care of himself. He left home when he was 15 and has been on his own ever since

8. When I was growing up, my mother often sent me to the neighborhood store to get something for her. And each time I went there, Mr. Ditmar, the owner,(give)...................... me a piece of candy

1. Use the right tense of the verbs in brackets
1. Please don't touch anything before the police (come)...............................................
2. "When............................................... penicillin(discover)......................................................? "In 1928"
3. It's at least a month sincce I last (see).......................................... Tom
4. People(speak)........................................ EL and French in Canada
5. The light (go)............................................ out while we were having tea
6. Glenda(work)................................... extremely hard when she was a student
7. The World War II(begin)....................................... in 1973 and(end)................................... in 1945
8. Who(hear)................................... the boss tell him that? Peter did
9. According to the research reports, people usually(turn)....................................... in their sleep 25 to 30 times each night
10. He had a bath, and then he(go)............................................. to bed
11. I(never, visit)........................................ Australia, but I(see)........................................ a program on TV about it two weeks ago