Cho biểu thức: P = (\(\frac{2}{x+2}-\frac{x}{x^2-4}\)); Q = \(\frac{x^2-2x}{x-4}\) (x ≠ 2; -2; 4)

a) rút gọn biểu thức P

b) tìm x để P . Q = \(\frac{2}{3}\)

c) tính giá trị của P biết x = 3

d) tìm x ∈ Z để P . Q nguyên

e) tính giá trị của x để P . Q > 1

f) tìm GTNN của P . Q khi x ≥ 0

nêu được những thuận lợi và khó khăn của sông ngòi đối với đời sống, sản xuất và sự cần thiết phải bảo vệ nguồn nước sông trong sạch.

1.the Pyramid is the ........ wonder you can still see today.

A. last B. early C. soon D. only

2. centuries ago, a list of seven wonders of the world was ......

A. put up B. written C. compiled D. take

3. There were other wonders which the ancient Greeks knew ..... about.

A. anything B. nothing C. something D. someone

4. Angkor Wat is one of the largest .... In the world.

A. temples B. churches C. pagodas D. tombs

5. Angkor Wat was originally built for .....

A. Hindus B. Buddhists C. Kings D. Queens

6. My class has ..... returned from a trip to the Grand Canyon in America.

A. only B. just C. yet D. before

7. Angkor Wat should really ..... as a wonder.

A. know B. known C. be know D. be known

8. Statue of Liberty was .... to the USA by the French.

A. constructed B. designed C. completed D. presented

9. I was born and .... in Hue, a beutiful city of Viet Nam.

A. grow up B. grew up C. growed up D. grown up

Combine each pair of sentences using "-ing" or "-ed"

1. I was woken up by a bell. The bell was ringing.

I ............................................................................

2. Some paintings were stolen from the museum. They haven't been found yet.

The painting ...........................................................

3. At the end of the street there is a path. The path leads to the river.

At the end ...............................................................

4. Some of the people can't come. They were invented to the party.

Some of ...............................................................

5. Most of the goods are exported. The goods are made in this factory.

Most of .................................................................

Underline and correct the mistake in each sentence.

1. James should be tell the news as soon as possible.

2. She asked Helen whether those shoes are too small for her.

3. It was late, so we decided taking a taxi home.

4. I wanted know who wrote the song.

5. She showed me where did I left my luggage.

6. A cup of coffee has made for you.

7. He let her going out alone.

8. She is proud of get mood mark.

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