Tìm các số nguyên x, y thoả mãn \(\frac{5}{x+y\sqrt{z}}-\frac{4}{x-y\sqrt{z}}+18\sqrt{2}=3\)

THỰC HIỆN PHÉP TÍNH \(\frac{1}{1-\sqrt{2}}-\frac{1}{\sqrt{2}-\sqrt{3}}+\frac{1}{\sqrt{3}-\sqrt{4}}-\frac{1}{\sqrt{4}-\sqrt{5}}+...+\frac{1}{\sqrt{99}-\sqrt{100}}\)

THỰC HIỆN PHÉP TÍNH \(\frac{\sqrt{2+\sqrt{3}}+\sqrt{2-\sqrt{3}}}{\sqrt{2+\sqrt{3}}-\sqrt{2-\sqrt{3}}}-\frac{\sqrt{2+\sqrt{3}}-\sqrt{2-\sqrt{3}}}{\sqrt{2+\sqrt{3}}+\sqrt{2-\sqrt{3}}}\)

Tìm lỗi sai và sửa lại

124. My friend was (A) crazy (B) although he was (C) informed of the news of his mother’s (D) death.

125. Thunder (A) is rarely heard beyond 15 miles (B) because of temperature (C) and wind vary at different (D) heights in the region around a thunderstorm.

Rewrite the sentences using the given words.

12-What would you do if you found some buried treasure? If you were……………..

13- If Paul hadn’t been interested, the project would have been abandoned. But for….

14- If by any chance you find my wallet, could you let me know? If you happen……..

15- I might be late. If so, start without me. If I……………………………………………

16- The fire was brought under control thanks to the night watch-man. If it hadn’t…...

17- Dick is in prison because a detective recognized him.

If a…………………………...

Từ đầu bài suy ra:

\(\left(x+y\right)+\left(y+z\right)+\left(z+x\right)=\frac{1}{2}+\frac{1}{3}+\frac{1}{4}\)

\(\Leftrightarrow x+y+y+z+z+x=\frac{13}{12}\)

\(\Leftrightarrow2x+2y+2z=\frac{13}{12}\)

\(\Leftrightarrow2\left(x+y+z\right)=\frac{13}{12}\)

\(\Rightarrow x+y+z=\frac{13}{12}:2=\frac{13}{24}\)

\(\Rightarrow x=\frac{13}{24}-\frac{1}{3}=\frac{5}{24}\)

\(y=\frac{13}{24}-\frac{1}{4}=\frac{7}{24}\)

\(z=\frac{13}{24}-\frac{1}{2}=\frac{1}{24}\)

Vậy...

Complete the second sentence with the same meaning.

1. He said: `` We must have a party to celebrate this`` -> He said that ....................

2. I'm on the tenth page of the letter I'm writing -> So far I ..........................

3. Minh last wrote to his pen pal five months ago. -> Minh hasn’t ..................

4. They usually wore jeans when they were young. -> They used................

5. We couldn’t go to school this morning because of the heavy rain. -> Because ...............

6. Practice speaking everyday or you can't improve your English. -> If ..........

7. Hard work is the secret of passing your exam. -> So long as.............................

8. You donot have to pay for elementary education in Viet Nam. -> Elementary education ..........

9. He was a fool to say that -> It is.........................................

10. Living in the city is exciting -> Some people find ..............................

Use the following sets of words and phrases to write complete sentences.

1. My uncle/ give up/ smoke / one year.

2. The noise / the traffice/ prevented /me/ go to sleep/

3. Look! / sun / set / mountains

4. In my life/ I / never be/ Pac Bo Cave.

5. It/ rain /./ I’d like / stay here / until / rain / stop.