Rút gọn B

B = \(\sqrt{x+4\sqrt{x-4}}+\sqrt{x-4\sqrt{x-4}}\)

A = \(\frac{\left(\sqrt{x}+\sqrt{y}\right)^2-4\sqrt{xy}}{\sqrt{x}-\sqrt{y}}\) \(-\frac{x\sqrt{y}+y\sqrt{x}}{\sqrt{xy}}\)

Chứng minh biểu thức trên không phụ thuộc vào giá trị của biến

Cho Q = \(\left(\frac{1}{\sqrt{x}-1}-\frac{1}{\sqrt{x}}\right):\left(\frac{\sqrt{x}+1}{\sqrt{x}-2}-\frac{\sqrt{x}+2}{\sqrt{x}-1}\right)\)

a. Tìm ĐKXĐ của Q?
b. Rút gọn Q?
c. Tìm x để Q>0

Fill each of blank spaces in this passage with ONE suitable word.
________had been an unusually peaceful evening, _________no arguments or disagreements, and Susan and Jack were reading comfortably in their chairs. Jack did not notice when Susan _________her book down. He turned a page and read several lines before she spoke.
"He was such a nice man" she said, as_________to herself.
Jack read as_________as the middle of the page before he really_________in what she had said. He looked over his book at her.
"Did you say something? he asked, _________ his place in the book with his finger.
Susan_________her head. "No, dear. It wasn't anything. I didn't _________ to interrupt. Just go on with your reading"
Jack_________her thoughtfully for a moment, and went back to his book. He tried to go on with his reading. It was impossible.

Complete each sentence with a phrase from box A followed by a phrase from box B. Do not use any phrase more than once.

A B

1. I will...

2. The plane...

3. The boy was told to...

4. Tom's grandmother....

5. It was a long time before she...

6. John....

7. We will have to...

8. The competition judges...

9. Daisy...

10. Think about it. Don't...

It appears to me that Sam is miserable at university.

--> As______________, Sam is miserable at university. (TELL)

he has been a journalist for 10 years

--> His career...

Cho tam giác ABC vuông tại A, AB<AC, AM là trung tuyến, AH là đường cao. Trên tia đối của MA lấy D sao cho MD = MA