\(\left(3x+1\right)^2=\left(3x+1\right)^4\)

\(\Rightarrow\left(3x+1\right)^2-\left(3x+1\right)^4=0\)

\(\Rightarrow\left(3x+1\right)^2\left[1-\left(3x+1\right)^2\right]=0\)

\(\Rightarrow\left[{}\begin{matrix}\left(3x+1\right)^2=0\\1-\left(3x+1\right)^2=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}3x+1=0\\\left(3x+1\right)^2=1\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}3x=-1\\3x+1=1\\3x+1=-1\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{-1}{3}\\3x=0\Rightarrow x=0\\3x=-2\Rightarrow x=\dfrac{-2}{3}\end{matrix}\right.\)

Vậy \(x\in\left\{\dfrac{-1}{3},0,\dfrac{-2}{3}\right\}\)

\(a,A=\dfrac{201220122012}{201320132013}=\dfrac{201220122012:100010001}{201320132013:100010001}=\dfrac{2012}{2013}\)

\(b,B=\dfrac{3.5.7.11.13.37-10101}{1212120+40404}=\dfrac{5.11.10101-10101}{10101.120+10101.4}=\dfrac{10101.\left(5.11-1\right)}{10101.\left(120+4\right)}=\dfrac{54}{124}=\dfrac{27}{62}\)

1. shoes

2. suit

3. raincoat

4. shorts

5. scarf

1. foot

2. ears

3. legs

4. mouth

5. teeth

giả sử

n² +2n+12 =k²

=>k² - n² =2(n+6)

=>(k+n)(k-n) =2(n+6)

=> k=6 ; n =4 

vậy n =4

1. A

2. E

3. D

4. B

5. F

1. A

2. A

3. A

4. B

5. C

Bray is a beautiful village about fifty kilometres west of London. A young Englishman named Howard Bonnier opened a restaurant called The Palace there about three and a half months ago. Not many people in Britain know Mr Bonnier’s name yet, but he’s already quite famous in France. This is because he has written in French magazines about almost all the best restaurants in that country. He’s only 29 years old.

When Howard was a teenager, he often went to restaurants with his mother and father.He liked doing this so much that he decided not to buy lots of clothes and CDs; instead, he used his money to visit France and eat in good restaurants. He also bought a lot of French and English cookbooks – he says he has more than two hundred and fifty!

So why did he decide to open a restaurant? Simply because he loves cooking. Has it been an easy thing to do? He says it’s expensive to start your own restaurant and it’s much more difficult to cook for fifty people than to cook for your family, but he’s sure he’s done the right thing.

1. The Palace há bên open for les than a year

A. Right B. Wrong C. Doesn't say

2. Lots of people in France know about Hward

A. Right B. Wrong C. Doesn't say

3. Howard's parents took him out to restaurants.

A. Right B. Wrong C. Doesn't say

4. Howard has always spent a lot of money on clothes.

A. Right B. Wrong C. Doesn't say

5. Howard has written books about Frech cooking.

A. Right B. Wrong C. Doesn't say

6. It cooks a lot of money to eat in Howard's restaurant.

A. Right B. Wrong C. Doesn't say

7. Howard says cooking for a lot of people is easy.

A. Right B. Wrong C. Doesn't say

1. key

2. glasses

3. money

4. comb

5. diary

haapy on the birthday