Tên: Trần Hương Thoan

Lớp: 2k4 (cái này chả lq j cả ==")

Link: Trần Hương Thoan

a, \(\dfrac{16}{2^n}=2\)

\(2^n=\dfrac{16}{2}\)

\(2^n=8\)

\(2^n=2^3\)

=> n = 3

b, \(\dfrac{\left(-3\right)^n}{81}=-27\)

\(\left(-3\right)^n=-27\cdot81\)

\(\left(-3\right)^n=\left(-3\right)^3\cdot3^4\)

\(\left(-3\right)^n=\left(-3\right)^7\)

=> n = 7

c, \(8^n:2^n=4\)

\(2^{3n}:2^n=2^2\)

\(2^{2n}=2^2\)

=> 2n = 2

n = 2:2

n = 1

cái này chỉ có những đứa ở trên được tag mới tl được à? thế thì t rút nhé, vì ko có tên t, đg định giải cho :)

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

Basic to any understanding of Canada in the 20 years after the Second World War is the country's impressive population growth. For every three Canadians in 1945, there were over five in 1966. In September 1966, Canada's population passed the 20 million mark. Most of this surging growth came from natural increase. The depression of the 1930s and the war had held back marriages, and the catching-up process began after 1945. The baby boom continued through the decade of the1950s, producing a population increase of nearly fifteen percent in the five years from 1951 to 1956. This rate of increase had been exceeded only once before in Canada's history, in the decade before 1911 when the prairies were being settled. Undoubtedly, the good economic conditions of the 1950s supported a growth in the population, but the expansion also derived from a trend toward earlier marriages and an increase in the average size of families. In 1957 the Canadian birth rate stood at 28 per thousand, one of the highest in the world.

After the peak year of 1957, the birth rate in Canada began to decline. It continued falling until in 1966 it stood at the lowest level in 25 years. Partly this decline reflected the low level of births during the depression and the war, but it was also caused by changes in Canadian society. Young people were staying at school longer; more women were working; young married couples were buying automobiles or houses before starting families; rising living standards were cutting down the size of families.

It appeared that Canada was once more falling in step with the trend toward smaller families that had occurred all through the Western world since the time of the Industrial Revolution. Although the growth in Canada's population had slowed down by 1966 (the increase in the first half of the 1960's was only nine percent), another large population wave was coming over the horizon. It would be composed of the children who were born during the period of the high birth rate prior to 1957.

What does the passage mainly discuss? 

A. Educational changes in Canadian society 

B. Canada during the Second World War 

C. Population trends in postwar Canada 

D. Standards of living in Canada 

a,He visited Hang Temple last month

(-) He didn't visit Hang Temple last month.

(?) Did he visit Hang Temple last month?

b,Ba sent letters to his parents

(-) Ba didn't send letters to his parents.

(?) Did Ba send letters to his parents?

c,Nam met Lan at the movie theater last night

(-) Nam didn't meet Lan at the movie theater last night.

(?) Did Nam meet Lan at the movie theater last night?

d,My father spent his summer vacation on the farm

(-) My father did not spend his summer vacation on the farm.

(?) Did you father spend his summer vacation on the farm?

e,The people were friendy

(-) The people were not friendly.

(?) Were the people friendly?

f,I was at home yesterday

(-) I wasn't at home yesterday.

(?) Were you at home yesterday?

Xét đa thức \(x^2-2x^2+2016\)

\(=x^2\cdot\left(1-2\right)+2016\)

\(=\left(-x\right)^2+2016\)

Vì \(\left(-x\right)^2\ge0\forall x\)

=> \(\left(-x\right)^2+2016\ge2016\forall x\)

Vậy đa thức trên vô nghiệm

1. What would he like to eat?

He would like to eat some noodles.

2. What would your mother like to read?

She would like to read the novels and woman magazines.

3. What would Lan like to drink?

She would like to drink lemon juice.

4. What would Nam like to see?

He would like to see a cowboy movie.

5. What would they like to play?

They would like to play volleyball and soccer.

6. What would you like to listen to?

We would like to listen to pop music.

7. What would her brother like to watch?

He would like to watch the contest programs.

8. WHat would you like to buy?

I would like to buy a box of chocolates.

1. I like taking part in sports.

2. There was a walking competition for school children last year.

3. The regular activity is a 5km walk to the beach on Sunday morning.

4. You should listen to the pool lifeguards .

5. They take a walk instead of riding their bicycles.

6. Are you aware of the time?

7. We carried out a survey for teenagers in the USA.

8. Children should always swim with an adult.