1,tìm a và b để đa thức x^4+ x^3+ax+4chia hết cho đa thức x^2-x+b

2,tìm giá trị nhỏ nhất đẻ biểu thức sau : A= 2x^2+2y^2-2xy-12y+2038

3,tìm giá trị nguyên của x để giá trị của biểu thức sau là nguyên tố:

A= 2x^3+x^2+2x+5/2x+1

4,tìm GTNN của biểu thức sau : A=(x-2)(x-5)(x^2-7x-10)

A=5x^2-14xy+10y^2-2y+2x+5

5,so sánh A= 2004.2006.(2005^2+1) và B=2005^2

Read of the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks

We are using up the world’s petroleum. We use it in our cars and to heat our building in winter. Farmers use petrochemicals to (24) ____ the soil rich. They use them to kill insects which eat plants. These chemicals go (25) ______ rivers and lakes and kill the fish there. Thousands of pollutants also go into the air and pollute it. Winds carry this (26) _____ air to other countries and other continents.

Poor farmers use the same land over and over The land needs a rest so it will be better next year. However, the farmers must have food this year. Poor people cut down forests for firewood. In some areas when the trees are gone, the land (27) ______ desert. Poor people can’t save the environment for the future .

This is not a problem for one country or one area of the world. It is a problem for all- humans. The people and the nations of the world must work together to (28) _______ the world’s resources.

Question 26

A. pollute

B. polluting

C. polluted

D. pollution

_______do you go to the amusement center? - Once a week.

A. How long

B. How far

C. How many

D. How often

Rearrange the words to make correct sentences.

in/ my father/ often/ the evening/ watches/ television/.

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.

Some scientists say that it is still not too late to minimize the effects of climate change_____enough money and effort are invested in correct projects.

A. in case

B. so that

C. even if

D. provided that