Dạng 3:

Bài 1:

a) Số lượng số hạng là:

\(\left(999-1\right):1+1=999\) (số hạng)

Tổng dãy là: 

\(A=\left(999+1\right)\cdot999:2=499500\)

b) Số lượng số hạng là:

\(\left(100-7\right):3+1=32\) (số hạng)

Tổng dãy là: 

\(S=\left(100+7\right)\cdot32:2=1712\)

3 careless

4 bleed

V

1 Hung has colllected stamps since 2000

2 The front yard isn't large enough to play soccer in

3 Milk is delivered twice a week by the milkman

4 When did you bought this computer?

5 His car doesn't run as fasst as a race car

6 Two languages can be spoken well by Lan

VI

1 T

2 F

3 T

4 T

VII

1 Mr. Nam is arriving in Hue tonight

2 They are going back to Englang in two months

3 It is not difficult to tránlate this sentence into English

4 Would you mind lending me your dictionary?

3 careless

4 bleed

V

1 Hung has colllected stamps since 2000

2 The front yard isn't large enough to play soccer in

3 Milk is delivered twice a week by the milkman

4 When did you bought this computer?

5 His car doesn't run as fasst as a race car

6 Two languages can be spoken well by Lan

VI

1 T

2 F

3 T

4 T

VII

1 Mr. Nam is arriving in Hue tonight

2 They are going back to Englang in two months

3 It is not difficult to tránlate this sentence into English

4 Would you mind lending me your dictionary?

mở bài là giới thiệu về cụ nha mn em viết lộn ạ 

thân bài là đóng góp ạ