1/8*2/6:3/4+5/3

=1/8*1/3:3/4+5/3

=1/24*4/3+5/3

=1/18+30/18

=31/18

Vì (x-10)^2 lớn hơn hoặc bằng 0

=) (x-10)^2 -25 lớn hơn hoặc bằng -25 

=)  Min b = -25 

Vậy Min b = 25

a) Ta có :

|x+2|= x+2 nếu x>-2 

          -x -2 nếu x<-2

Th1 x>-2

x+2 = x+2

0=0

=) x>-2

Th2 tg tự ý b cũng z

1. When did he ( leave ) leave for work last week?

2. What did you ( do ) do yesterday ?

3. We ( begin ) began to learn english 3 years ago.

4. She ( be ) was an engineer last week.

5. Lan ( be not ) isn't at home yesterday.

6. He ( wear ) wore the shirt last week.

7. They ( be ) were here yesterday.

8. Did you ( go ) go to school yesterday ?

9. Was Tam ( be ) at home last night ? - Yes , he ( be ) was.

10. Where did he ( go ) go yesterday ?

11. I ( be ) was sick last night.

12. Why didn't you ( not come ) come to class yesterday ?

13. Were we ( be ) in the library yesterday ?

14. Hoa ( buy ) bought a lot of things for her birthday party.

1. I ( go ) go to school everyday.

2. I ( go ) went to school yesterday.

3. She ( play ) plays table tennis every afternoon.

4. She ( play ) played table tennis last week.

5. Last week I ten years old but I am eleven now.

6. Where were you at nine o' clock last Friday afternoon?

7. Are you tired now ?

8. We ( go ) went to the beach yesterday.

9. I ( love ) love this teddy bear.

10. Sam ( sell) sold his computer yesterday.

Có tất cả số trong dãy số là:(2015-1)+1:1=2015

Tổng là:(2015+1)x2015:2=4062240

CÁc số nguyên x thỏa mãn là:    x=8 hoặc x= -9

ae k cho cao nguyen thu uyen xinh gái coi, thằng nào không k tao chém chết

dat bieu thuc tren la A ta co:

A = 3 x 4 + 4 x 5 + 5 x 6+ ...+ 149 x 150

3A= 3 x 4 x 3+4 x 5 x3+...+ 149 x 150 x 3

3A=3 x 4 x(5-2)+4x5x(6-3)+...+149 x 150 x(151-148)

3A = 3 x 4 x 5 - 2 x 3 x 4+4 x 5 x 6- 3 x 4 x 5+...+149 x 150 x 151 - 148 x 149 x 150

3A= 149 x 150 x 151 

=>A= 149 x 50 x 151 

A= 1124950

tùy theo từng hình bạn ơi