1 Cho n(n+1) là tích 2 số tự nhiên liên tiếp thì chia hết cho 2 .

Chứng minh: a, 3n mũ 2 + n chia hết

b, (4n mũ 2 + 4n ) + 8n + 16 chia hết 8

2 , Chứng minh:C = 1 + 3 + 3 mũ 2 + 3 mũ 3 + .........+ 3 mũ 11 chia hết 13

3 , Tìm số dư của : a, 2004 mũ 2004 khi chia cho 11

b, 776 mũ 776 + 777 mũ 777 + 778 mũ 778 khi chia cho 3 , 5

4 , Chứng minh : 9 mũ 2002 - 1 chia hết 18

5 , Chứng minh : 7 mũ 214 - 4 chia hết 3

6 , Chứng minh : 4 mũ 200 + 3 mũ 1002 chia hết 13

Read 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 from 31 to 35.

In Germany, it's important to be serious in a work situation. They don't mix work and play so you shouldn't make jokes (31) ______ you do in the UK and USA when you first meet people. They work in a very organized way and prefer to do one thing at a time. They don't like interruptions or (32) ______changes of schedule. Punctuality is very important so you should arrive on time for appointments. At meeting, it’s important to follow the agenda and not interrupt (33) ______speaker. If you give a presentation, you should focus (34) ______ facts and technical information and the quality of your company's products. You should also prepare well, as they may ask a lot of questions. Colleagues normally use the family names, and title - for example 'Doctor' or 'Professor', so you shouldn't use first names (35) ______ a person asks you to.

Điền vào ô 34.

A. on

B. to

C. at

D. in

Mark the letter A, B, C or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions.

Sports and festivals form an integral part of every human society.

A. informative

B. delighted

C. exciting

D. essentia