1/Tính giá trị của biểu thức

a. x^2 + 6 x + 9 với x = 9997

b. x^3 - 12x^2 + 48 x-64 với x = 4

c. x^3 - 3x^2 + 3 x - 1 với x= 11

d. 49x^2 - 70x + 25 với x= 5

2/. Tìm x, biết

a. ( x+ 3 ) . (x^2 - 3x + 9 ) - x. ( x-1) .(x+1) = 14

b. (x+1 ) . (x^2 _x+1) - x. (x-3) . (x+3) =-27

c. 3.(x-1)^2 - 3x . (x-5 ) =1

d. (x-3) . (x^2+3x + 9) + x.(x+2)_ . (2_x) = 1

Viết các biểu thức sau dưới dạng bình phương hoặc lập phương của 1 tổng 1 hiệu

a.x^2 -5x +25/a

b.16x^2 - 8 x + 1

c. 4x^2 + 12xy + 9 y^2

d. x^3 + 3X ^2 + 3x +1

e. 27 y ^3 -9y^2 + y - 1/27

f. 8x^6 + 12x^4y +6 x^2 y^2 +y ^2

This room is too dirty. You should ______ it now.(to clean,cleaning, clean)

1. Remember not to park in front of a zebra……………..

A. crossing B. cross C. crossed D. across

2. …………….we lost the game, we were happy that we played well.

A. Although B. Because C. If D. Nevertheless

3. We………..drink water from the tap without boiling it first.

A. never should B. should never C. should not to D. not should

4. Van Gogh was famous for his…………………of the countryside around Arles in the South of France.

A. portraits B. watercolours C. landscapes D. crayons

5. “Recycling” means creating new products from…………….materials.

A. use B. using C. used D. to use

6. While formerly a member of the sports club, Mr. Teeters……………tennis there regularly.

A. is used to playing B. used to play C. was used to play D. used to playing

7. Drinking and driving of one of the most common……………….of traffic accidents.

A. reasons B. effects C. sources D. causes

8. Solar energy - one type…………………sources – is being used more and more.

A. renewable B. non-renewable C. renewing D. renewed

9. –“Does that red motorbike belong to your mother?”

- “No, ………………….is white.”

A. she B. her C. hers D. mine

10. Overpopulation causes a lot of problems,………..?

A. isn’t it B. doesn’t it C. do they D. don’t they

11.Nuclear power ...............................in the future.

A. will replace B. replaced C. will be replaced D. replaces

12.My father .............a lot last year, but this year he doesn’t any more.

A. smokes B. used to smoke C. smoking D. gets used to smoke

13.It’s really difficult to .......................a bicycle up the hill

A. fly B. drive C. pedal D. sail

14.At this time next week, we .................a test on sources of energy

A. will take B. take C. will be taking D. are taking

15.My children often sleep while they are ................a plane.

A. in B. on C. by D. 0

16............books are here. ..............are there.

A.Theirs / ours B. Their / our C. Theirs / our D. Their / ours

choose the word having the underlined part pronounced differently in each line