1. Where do you live?

2. Where does Minh' mother work?

3. Where do they work?

4. What school does she go to?

5. How many brothers and sisters do you have?

6. How many bookstores are there near your house?

7. Where does he work?

8. Where do you eat?

a)\(1+\sqrt{3x+1}=3x\)\(\Leftrightarrow\sqrt{3x+1}=3x-1\Leftrightarrow3x+1=\left(3x-1\right)^2\)

\(\Leftrightarrow3x-1=9x^2-6x+1\Leftrightarrow9x^2-6x+1-3x+1=0\)

\(\Leftrightarrow9x^2-9x+2=0\Leftrightarrow9x^2-6x-3x+2=0\)

\(\Leftrightarrow3x\cdot\left(3x-2\right)-\left(3x-2\right)=0\Leftrightarrow\left(3x-1\right)\left(3x-2\right)=0\)

\(\Leftrightarrow\left[\begin{array}{nghiempt}3x-1=0\\3x-2=0\end{cases}\Leftrightarrow\left[\begin{array}{nghiempt}x=\frac{1}{3}\\x=\frac{2}{3\left[\right]}\end{array}\right.}\)

a. \(\frac{26}{5-2\sqrt{3}}\)=\(\frac{26\cdot\left(5+2\sqrt{3}\right)}{\left(5-2\sqrt{3}\right)\left(5+2\sqrt{3}\right)}\)=\(\frac{26\cdot\left(5+2\sqrt{3}\right)}{5^2-\left(2\sqrt{3}\right)^2}=\frac{26\cdot\left(5+2\sqrt{3}\right)}{13}=2\cdot\left(5+2\sqrt{3}\right)=10+4\sqrt{3}\)

b.\(\frac{9-2\sqrt{3}}{3\sqrt{6}-2\sqrt{2}}=\frac{\sqrt{3}\cdot\left(3\sqrt{3}-2\right)}{\sqrt{2}\cdot\left(3\sqrt{3}-2\right)}=\frac{\sqrt{3}}{\sqrt{2}}=\frac{\sqrt{6}}{2}\)

c.\(\frac{2\sqrt{10}-5}{4-\sqrt{10}}=\frac{\sqrt{5}\cdot\left(2\sqrt{2}-\sqrt{5}\right)}{\sqrt{2}\cdot\left(2\sqrt{2}-\sqrt{5}\right)}=\frac{\sqrt{5}}{\sqrt{2}}=\frac{\sqrt{10}}{2}\)

d.\(2\sqrt{5}-\sqrt{125}-\sqrt{80}+\sqrt{605}=2\sqrt{5}-5\sqrt{5}-4\sqrt{5}+11\sqrt{5}\)=\(4\sqrt{5}\)

Chất nào sau đây có nhiệt độ sôi cao nhất?

A. CH₃COOH     

B. CH₃CHO 

C. C₂H₅OH 

D. C₂H₆

1. Mr.Hoang spent half an hour walking to work yesterday.

2. How much is this cap?

3. You'd better not eat too much meat.

4. Lan has two older sisters.

5. Our house is the oldest in the living centre.

6. Mai is usually a hard woker.

7. Hoa's collection has eight hundred stamps.

8. What is the weight of the chicken?

9. What is the price of this book?

10. I prefer listening to music to watching TV.

Gợi ý cho các bạn là 18 và 14 nghen chỉ like 10 bạn thôi nhé

Mary didn't buy any books because the bookshop closed ten minute ago.

               A                                 B                                     C                   D 

Sai: D. minute ago => minutes ago

11999, tớ mới làm hồi sáng, trong violympic đúng không?

1. Walking in the rain is very dangerous.

2. You mustn't eat food in the classroom.