bai nay minh chua bao gio gap

\(A=\frac{1}{1^2}+\frac{1}{2^2}+...+\frac{1}{50^2}\)

Có: \(\hept{\begin{cases}\frac{1}{1^2}>\frac{1}{1\times2}\\...\\\frac{1}{50^2}>\frac{1}{50\times51}\end{cases}}\)

\(\Rightarrow A>\frac{1}{1\times2}+\frac{1}{2\times3}+...+\frac{1}{50\times51}\)

\(\Rightarrow A>1-\frac{1}{51}\)

\(\Rightarrow A>\frac{50}{51}\)

Nửa chu vi HCN là:

28 : 2 = 14 (cm)

Chiều rộng HCN là:

18 : 3 = 6 (cm)

Chiều dài HCN là:

14 - 6 = 8 (cm)

Diện tích HCN là:

8 x 6 = 48 (cm²)

k cho mình nhé:)

1.My name is Huong(Tôi tên là Hương)

2.I'm fine,thank you(Tôi ổn,cảm ơn)
3.I'm nine years old(Tôi 9 tuổi)
4.H-U-O-N-G

5.I play hide and seek(Tôi chơi trốn tìm)

sách lớp mấy vậy

1➩5 : My

1. my name is Nguyen Phuong Chi, you can call me Chi for short

2. it's c-h-i

3. now, i'm 10 old

4. i'm great today :>

l'm Trí

• bus (N) → buses
• go (V) → goes
• do (V) → does
• watch (V) → watches
• visit (V) → visits
• brush (V) → brushes
• piano (N) → pianos
• video (N) → videos
• tomato (N) → tomatoes
• listen (V) → listens
• octobus (bạn viết nhầm, đúng phải là octopus) → octopuses (hoặc octopi, nhưng thông dụng hơn là octopuses)
• pencil (N) → pencils
• kilo (N) → kilos
• snake (N) → snakes
• play (V) → plays
• wash (V) → washes
• touch (V) → touches
• looks (V) → (từ gốc phải là look) → looks
• box (N) → boxes
• drink (V) → drinks

1.bus -> buses

2.go -> goes

3.do -> does

4.watch -> watches

5.visit -> visits

6.brush -> brushes

7.piano -> pianos

8.video -> videos

9.tomato -> tomatoes

10.listen -> listens

11.octobus -> octopuses

12.pencil -> pencils

13.kilo -> kilos

14.snake -> snakes

15.play -> plays

16.wash -> washes

17.touch -> touches

18.looks -> looks

19.box -> boxes

20.drink -> drinks

1.runs

2.flies

3.cries

4.fixes

5.does

1.runs

2.flies

3.cries

4.fixes

5.does

6.watches

7.cooks

8.eats

9.writes

10.catches

11.kisses

12.likes

13.plays

14..dances

15.tries

16.studies

17.buys

18.carries

19.swims

20.wears

1) My

2) his

3) This

4) This

5) My

6) I

7) they

8) hẻ/ his, its

9) she/ he/ it

10) you

Hình như sai á bn, mk ko chắc nữa

1.my

2.his

3.she

4.he

5.our

6.I

7.we

8.your

9.it

10.they

Đặt các trạng từ chỉ tần suất vào vị trí đúng ở câu

4. Peter doesn’t usually get up before seven. (usually)

5. They never watch TV in the afternoon (never)

TL:

Đặt các trạng từ chỉ tần xuất vào vị trí đúng ở câu

4,peter doens't usualy get up before seven.

5.they never watch TV in the afternoon.

~HT

my name is cong 

I am twelve years old

My family has four people

oh I can make friend with you

my name is Mai

i am eleven years old

there are four people in my family