Bài 1.

1.I get to work in half an hour

It takes me half an hour to get to work.

2.the restaurant is on the left of the bookstore

The bookstore is on the right of the restaurant.

3.how much is this dictionary?

how much does this dictionary cost?

4.It isn't important for you to finish the work today

You don't have to finish the work today.

5.There are over eight hundred stamps in Tom's collection

Tom's collection has over eight hundred stamps.

6.we enjoy playing football very much

We are interested in playing football / We are fond of playing football.

7.the library contains over 30 milion books

There are over 30 million books in the library.

8.how terrible the weather is !

What terrible weather!

Phân số chỉ số phần quãng đường người đi xe máy đi giờ thứ ba là :

1 - 2/5 - 1/3 = 4/15 ( quãng đường )

Quãng đường AB là :

44 : 4/15 = 165 ( km )

       Đáp số : 165 km

1/ 3(x - 4) - (8 - x) = 12 => 3x - 12 - 8 + x = 12 => 4x = 32 => x = 8

2/ 4(x - 5) - 3(x - 7) = -9 => 4x - 20 - 3x + 21 = -9 => x = -10

3/ 7(x - 3) -5(3 - x) = 11x - 5 => 7x - 21 - 15 + 5x = 11x - 5 => x = 31

4/ -5(2 - x) + 4(x - 3) = 10x => -10 + 5x + 4x - 12 = 10x => x = -22

1.The bookstore is between the bakery and the museum

2. they live at 58 Rading street

3.Could you show me the way to the restaurant ?

4.The restaurant is to the right of thehotel

5.how often do you write a letter to your pen pal ?

6.my father goes to work by car

7.can you take a photograph for me ?

8.we often go to Nha Trang beach on summer vacation

Để PT có hai nghiệm phân biệt thì \(\Delta'=\left(m+1\right)^2-\left(m^2+2\right)=2m-1>0\Leftrightarrow m>\frac{1}{2}\)

Áp dụng định lí Viet, ta có :

\(\left\{\begin{matrix}x_1+x_2=2\left(m+1\right)\\x_1.x_2=m^2+2\end{matrix}\right.\)

Mà \(x_1^2+x_2^2=10\) nên ta có \(4\left(m+1\right)^2-2.\left(m^2+2\right)=10\Leftrightarrow2m^2+8m-10=0\)

\(\Leftrightarrow\left[\begin{matrix}m=1\\m=-5\end{matrix}\right.\) (loại nghiệm m = -5 vì không thỏa điều kiện)

Vậy m = 1

Áp dụng \(1+2+...+k=\frac{k\left(k+1\right)}{2}\) thì ta được :

\(\sqrt{\left[1+2+3+...+\left(n-1\right)+n\right]+\left[n+\left(n-1\right)+...+3+2+1\right]-n}=2010\)

\(\Leftrightarrow\sqrt{2.\frac{n\left(n+1\right)}{2}-n}=2010\)

\(\Leftrightarrow\sqrt{n^2}=2010\Leftrightarrow n=2010\)

phân số ứng với số lít dầu thùng thứ 3 là

1-1/6-3/8=11/24 

số lít dầu thùng thứ 3 là

72x11/24=33(lít)

ĐS:33 lít

Từ \(10x^2+5x-3=0\) suy ra \(x^2+5x-2=-9x^2+1\) thay vào P được

\(P=\frac{3\left(x^2+5x-2\right)}{9x^2-1}=\frac{3\left(-9x^2+1\right)}{9x^2-1}=\frac{-3\left(9x^2-1\right)}{9x^2-1}=-3\)

a/ Xét với \(x\ge3\) thì PT đã cho trở thành \(\left(x-3\right)-x=7\Leftrightarrow-3=7\) (vô lí)

Xét với x<3 thì PT đã cho trở thành \(\left(3-x\right)-x=7\Leftrightarrow x=-2\) (thỏa mãn)

Vậy x = -2

b/ Tương tự như trên

c/ \(\left|2x+8\right|+4x=10\Leftrightarrow\left|x+4\right|+2x=5\)

Xét với \(x\ge-4\) thì PT đã cho trở thành \(\left(x+4\right)+2x=5\Leftrightarrow x=\frac{1}{3}\) (thỏa mãn)

Xét với x < -4 thì PT đã cho trở thành \(\left(-4-x\right)+2x=10\Leftrightarrow x=14\) (vô lí)

Vậy x = 1/3

6. I’ve never read a more romatic story.

It’s the first time I have read a more romantic story.

7. No one works harder than Barbara.

Barbara works the hardest.

8. I haven’t met him for two years.

It’s two years since I met him.

9. Richard can cook very well.

Richard is a good cook.

10. The water was so cold that the children could not swim in it.

The water was not hot enough for the children to swim in.