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27 tháng 4 2018

Nhớ rằng: \(\frac{n}{a.\left(a+n\right)}=\frac{1}{a}+\frac{1}{a+n}\)

Ta có: \(A=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{90}\)

           \(A=\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{9.10}\)

Áp dụng công thức trên, ta có:

            \(A=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{9}-\frac{1}{10}\)

             \(A=1-\frac{1}{10}=\frac{9}{10}\)

27 tháng 4 2018

\(Â=\frac{9}{10}\)

IV. Read and answer.Hi . My name is Rosy. I’m eight years old . This is a picture of my family. My father is ateacher. He likes watching films . His favourite food is fish .This is my mother . My motheris a nurse . She usually listens to music in her free time . She likes vegetables and beef . Mybrother is a student . He’s six years old . His favourite drink is orange juice . He also likeshamburger1. What is her name ? Her name is Rosy.2. How old is Rosy...
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IV. Read and answer.
Hi . My name is Rosy. I’m eight years old . This is a picture of my family. My father is a
teacher. He likes watching films . His favourite food is fish .This is my mother . My mother
is a nurse . She usually listens to music in her free time . She likes vegetables and beef . My
brother is a student . He’s six years old . His favourite drink is orange juice . He also likes
hamburger
1. What is her name ? Her name is Rosy.
2. How old is Rosy ?

…………………………………………………………………………….
3. What does her father do ?
…………………………………………………………………………….
4. What is Rosy’s father favourite food?
…………………………………………………………………………….
5. What does her mother do ?
…………………………………………………………………………….
6. What is Rosy’s mother favourite food?
…………………………………………………………………………….
7. How old is her brother ?
…………………………………………………………………………….
8. What is Rosy’s brother favourite drink ?
…………………………………………………………………………….
9. What food does he like ?
…………………………………………………………………………….
 

1
16 tháng 3 2022

1. Her name is Rosy.   2. She’s eight years old.    3. Her father is ateacher    4. Rosy’s father favorite food is fish.   5. Her mother is a nurse.

6. Rosy’s mother favorite food are vegetables and beef.   7. Her brother is six years old.   8. Rosy’s brother favorite drink is orange juice.

9. He s hamburger.

10 tháng 1 2022

2. visit

3. play

4. works

5. doesn't work

6. don't speak

7. doesn't go

8. don't clean

9. doesn't ride

10. doesn't work

11. Does - make

12. Does - write

13. Does - speak

14. Does - phone

15. Does - play

10 tháng 1 2022

Put the correct verb in present simple :

1. I usually go (go) to school.

2. They  visit   (visit) us often.

3. You play  (play) basketball once a week.

4. Tom works (work) every day.

5. My father doesn't work (not work) at school.

6. You don't speak (not speak) English.

7. He doesn't go (not go) home late.

8. They don't clean ( not clean ) the bathroom.

9. Mai doesn't ride ( not ride ) her bike in the park.

10. Billy doesn't work (not work) in the supermarket.

11. Does her mother make (make) breakfast every day?

12. Does she write ( write ) a letter ?

13. Does Linda speak (speak) English?

14. Does  Peter phone (phone) his father on Sundays?

15. Does  Ann play (play) basketball very well?

LUYỆN VIOLYMPIC TIẾNG ANH LỚP 4 (2021-2022)Câu 1: The sum of all one digit numbers?Câu 2: Which value is not equal to 4500? (45tens, 450tens, 45 hundred)Câu 3: Which number below is the word form of 20 300?Câu 4: How many two digit odd numbers are there that are greater than 15?Câu 5: Lily writers a number. It has the digit 5 in the thousands place and the digit 8 in the units place. Which of these numbers could Lily have written?Câu 6: What is the smallest posible number that can...
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LUYỆN VIOLYMPIC TIẾNG ANH LỚP 4 (2021-2022)

Câu 1: The sum of all one digit numbers?

Câu 2: Which value is not equal to 4500? (45tens, 450tens, 45 hundred)

Câu 3: Which number below is the word form of 20 300?

Câu 4: How many two digit odd numbers are there that are greater than 15?

Câu 5: Lily writers a number. It has the digit 5 in the thousands place and the digit 8 in the units place. Which of these numbers could Lily have written?

Câu 6: What is the smallest posible number that can be written using the digits 4, 7, 0, 6? (use each digit only once)

Câu 7: If the sum of three consecutive natural numbers is less than 90, find the largest possible value of the largest natural number is?

Câu 8: How many multiples of 4 lie between 1000 and 2500?

Câu 9: Read number: 35 206 :...........................................................

Câu 10: Jack finished the bicycle race with a time of 34152 seconds, Jane finished with a time of 34215 seconds, and Tina finished with a time of 34125 seconds. In what order did they finish the race?

Câu 11: The The greatest odd number that can be formed by all the digit 1,2,0 and 8 is?

Câu 12: A rectangle having length and breadth are 25cm and 8cm respectively. The perimeter of the rectangle?

Câu 13: Amy put 50 photographs into an online photo album. On each page she could fit eight photos. How many photos were on the last page?

Câu 14: Bon is 5 years old. Ben’s age is 3 years more than the double of Bon’s age. Find the age of Ben?

Câu 15: Which value is equal to 56 hundreds? (56000; 5600 tens; 560 tens; 56 units)

Câu 16:What is the perimeter of  a square with side lengths of 205 cm?  

Câu 17: What is the greatest 3-digit number whose digits total is 13?

Câu 18: Anna has a chocolate chip cookie recipe that makes 60 cookies and calls for 6cups of flour. If he only wants to make 40 cookies. How many cups of flour would he need?

Câu 19: A string of 5m35cm was cut into 5 equal parts. What’s the length of each part in cm?

                      Giúp mình với!

4
4 tháng 12 2021

DỊCH HAY GÌ THẾ BẠN

4 tháng 12 2021

@Nguyễn Thị Cúc

 Giải ra nha bạn!

I. PHONICS1.A.this                       B.thin                   C.thick                       D.thanks2.A. small                B. tall                       C.bad                        D.ball3.A. room                B.door                     C.school                    D.book4.A.when                ...
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I. PHONICS

1.A.this                       B.thin                   C.thick                       D.thanks

2.A. small                B. tall                       C.bad                        D.ball

3.A. room                B.door                     C.school                    D.book

4.A.when                  B.why                        C.who                        D.where

5.A.nose                  B.cold                       C. hold                      D. flower   

6.A. large                 B. bad                      C.fat                         D.handsome

7.A. Bay                  B. play                     C.stay                      D.watch

8.A.brother              B.open                      C.so                        D.cold

9. A. take                   B. late                       C. table                    D. fall

10.A.nose                   B.flower                  C.hold                       D. cold  

3

I. PHONICS

1.A.this  

2.A. small 

3 B.door 

4. C.who 

5 D. flower   

6.D.handsome

7. D.watch

8.A.brother 

9. D. fall

10.A.nose                   B.flower                  C.hold                       D. cold  

30 tháng 7 2021

I. PHONICS

1.A.this                       B.thin                   C.thick                       D.thanks

2.A. small                B. tall                       C.bad                        D.ball

3.A. room                B.door                     C.school                    D.book

4.A.when                  B.why                        C.who                        D.where

5.A.nose                  B.cold                       C. hold                      D. flower   

6.A. large                 B. bad                      C.fat                         D.handsome

7.A. Bay                  B. play                     C.stay                      D.watch

8.A.brother              B.open                      C.so                        D.cold

9. A. take                   B. late                       C. table                    D. fall

10.A.nose                   B.flower                  C.hold                       D. cold  

* Nếu sai thì thông cảm ạ :) *

24 tháng 5 2019

\(A=\frac{1}{3}.\left(\frac{3}{2.4.6}+\frac{3}{4.6.8}+...+\frac{3}{22.24.26}\right)\)

\(A=\frac{1}{3}.\left(\frac{1}{2.4}-\frac{1}{4.6}+\frac{1}{4.6}-\frac{1}{6.8}+...+\frac{1}{22.24}-\frac{1}{24.26}\right)\)

\(A=\frac{1}{3}.\left(\frac{1}{2.4}-\frac{1}{24.26}\right)\)

\(A=\frac{1}{3}.\frac{77}{624}\)

\(A=\frac{77}{1872}\)

1. They (do) it for you tomorrow.2. My father (call) you in 5 minutes.4. We believe that she (recover) from her illness soon.5.  I promise I (return) school on time.6. If it rains, he (stay) at home.7. You (take) me to the zoo this weekend?8. I think he (not come) back his hometown.Bài 2: Dùng từ gợi ý viết thành câu hoàn chỉnh.1. She/ hope/ that/ Mary/ come/ party/ tonight.…………………………………………………………………………2. I/ finish/ my...
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1. They (do) it for you tomorrow.

2. My father (call) you in 5 minutes.

4. We believe that she (recover) from her illness soon.

5.  I promise I (return) school on time.

6. If it rains, he (stay) at home.

7. You (take) me to the zoo this weekend?

8. I think he (not come) back his hometown.

Bài 2: Dùng từ gợi ý viết thành câu hoàn chỉnh.

1. She/ hope/ that/ Mary/ come/ party/ tonight.

…………………………………………………………………………

2. I/ finish/ my report/ 2 days.

…………………………………………………………………………

3. If/ you/ not/ study/ hard/,/ you/ not/ pass/ final/ exam.

…………………………………………………………………………

4. You/ look/ tired,/ so/ I/ bring/ you/ something/ eat.

…………………………………………………………………………

5. you/ please/ give/ me/ lift/ station?

…………………………………………………………………………

 bài 1 là chia động từ

3
30 tháng 10 2021

Bài 1

1.will do 

2.calls

4. wil recover

5. return

6.will stay

7. are going to table

8. doén't come

30 tháng 10 2021

hộ mình bài 2 luôn cảm ơn 

Name: Nguyễn Minh Quân     Class: 4CI. Correct the mistakes.1.     Where do your mother often buy this book?     ______________________________________2.     Are Tom studying?                            ______________________________________3.     Hoa not have good speaking skill.               ______________________________________4.     The young girl not writing the letter now.           ...
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Name: Nguyễn Minh Quân     Class: 4C

I. Correct the mistakes.

1.     Where do your mother often buy this book?     ______________________________________

2.     Are Tom studying?                            ______________________________________

3.     Hoa not have good speaking skill.               ______________________________________

4.     The young girl not writing the letter now.            ______________________________________

5.     Are Lam fond of listening to music?     ______________________________________

6.     They studies math.                             ______________________________________

7.     What you usually do in the morning?     ______________________________________

8.     They travel to London tomorrow.      ______________________________________

9.     The plane is land now.                       ______________________________________

10.            Why she is saying loudly?                      ______________________________________

2
24 tháng 8 2021

1. Where do your mother often buy this book? => Where does your mother often buy this book?
2. Are Tom studying? => Is Tom studying?
3. Hoa not have good speaking skill. => Hoa does not have good speaking skill
4. The young girl not writing the letter now. => The young girl is not writing the letter now.
5. Are Lam fond of listening music?=> Is Lam fond of listening to music?
6. They studies math=> They study math
7. What you usually do in the morning? => What do you usually do in the morning?
8. They are traveling to London. => Th ey are travelling to London.
9. The plane is land now.=> The plane is landing now
10. Why she is saying loudly?=> Why is she saying loudly?

24 tháng 8 2021

1. Where do your mother often buy this book?

=> Where does your mother often buy this book?
2. Are Tom studying English now?

=>Is tom studying English now?
3. Hoa not have good speaking skill.

=>Hoa doesn't have good speaking skill.

4. The young girl not writing the letter now.

=> That young girl isn't writing the letter now.

5. Are Lam fond of listening music?

=> Does Lam fond of listening to music?

6. They studies math once time a week.

=> They study math once time a week.

7. What you usually do in the morning?

=> What do you usually do in the morning?

8. They are traveling to London.

=>They are travelling to London.

9. The plane is land now.

=> The plane is landing now.

10. Why she is saying loudly?

=> why is she saying loudly?

Hok tốt

He ....................................................................1.      Phuong/, /build/ Tuan/ and/ Hoa/ may/ beach/ sandcastles /the/on/...................................................................................................................................................2.      My/ will/ the/ family/ and/ sea/ I/...
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He ....................................................................

1.      Phuong/, /build/ Tuan/ and/ Hoa/ may/ beach/ sandcastles /the/on/.

..................................................................................................................................................

2.      My/ will/ the/ family/ and/ sea/ I/ swim/in/.

..................................................................................................................................................

3.      Seaside/ They’ll /be /the/ on/ at/Sunday/.

..................................................................................................................................................

4.      islands/ She’ll /Monday/ visit/ the/on/.

..................................................................................................................................................

5.      be/ Where/ will/ Saturday/ you/on/?

..................................................................................................................................................

6.      and /I /think /school /Mai/ I /be /at/will/.

..................................................................................................................................................

7.      countryside /The/ will /month /boys/ be/ in/ the/next/.

..................................................................................................................................................

8.      I/ think/ tomorrow/ I’ll /the/ mountains/visit/.

..................................................................................................................................................

9.      countryside /We /picnic/ will/ for/ a/ in/ go/the/.

..................................................................................................................................................

10.  week/ the/ They/ seaside/ will/ be/ at/next/.

..................................................................................................................................................

7
31 tháng 10 2021

mình cần gấp các bạn giúp mình đánh hơi lâu cững được

31 tháng 10 2021

1.Phuong,Tuan,Hoa may build a sandcastle on the beach.

2.My family and i will swim in the sea.