Hmm đề bài sao đy , là sắp xếp hay sao đy nhỉ

cậu thpt à

đâu cs đâu

hhh, mk ghi lộn ó mak

7.15 : 0.5 + 7.15 x 9 - 7.15

= 14.3 + 7.15 x ( 9 - 1 )

= 14.3 + 7.15 x 8

= 14.3 +  57.2

= 71.5

7,15 :( 0,5+9 -1 ) 

7,15 : 0,5 + 7,15 x 9 -7,15

= 7,15 x 2 +7,15 x 9 - 7,15 x 1

= 7,15 x (2+9-1)

=7,15 x 10

= 71,5

ta thấy (x+1)(2y-5)=143=11.13=13.11=143.1=1.143

Suy ra ta có 4 trường hợp sau:

Nếu x + 1 = 11 suy ra ta x = 10 ; 2y - 5 = 13 suy ra y = 9

Nếu y + 1 = 13 suy ra y = 12 ; 2y-5=11 suy ra  y = 8 

Nếu x + 1 = 143 suy ra x = 142 ; 2y - 5 = 1 suy ra y = 3

Nếu x + 1 = 1 suy ra x = 0 ; 2y - 5 = 143 suy ra y = 74

Vậy x = 10 thì y = 9

 x = 12 thì y = 8

x = 142 thì y = 3

x = 0 thì y = 74

Vì (x+1)(2y-5) = 143 => x+1;2y-5 \(\in\)Ư(143) = {1;11;13;143}

Ta có:

Nếu x+1=1;2y-5=143=> x=0;y=74

Nếu x+1=11;2y-5=13=>x=10;y=9

Nếu x+1=13;2y-5=11=>x=12;y=8

Nếu x+1=143;2y-1=1=>x=142;y=0

Vậy (x;y) \(\in\){(0;74);(10;9);(12;8);(142;0)

^^

Of all the subjects taught in school, I Geography best. It is the only subject which teaches me everything I need to know about the world we live in, for example, vegetation, way of life of people, climate, agriculture and economy.

I learn about the countries around Malaysia and in other parts of the world and, since I cannot visit and see for myself every country in the world, I get at least a good picture of these countries by studying Geography. I am very interested in finding out more about other countries especially those that experience snow when winter comes. I often wonder about the life of the people in these countries. What would it be to be dressed in thick clothes and boots and living in snow-covered houses amidst fir trees? Then, there are the hot desert lands that stretch for miles and miles without a tree in sight. They, too, fascinate me. I marvel at the inhabitants who are able to tolerate the intense heat of the burning sun, traveling along miles of barren, hot land on camels where the only vegetation found would be the few palm trees growing at an oasis. The wide range of food which we enjoy daily such as butter, cheese, fruits, bread that comes from wheat and many others lead me on to find out how they are processed and imported into Malaysia and finally make their appearance in our homes.

As I study more in Geography, I understand better the changes in weather conditions, for example, why there are hot and dry seasons or cool rainy days during the monsoon season and how deserts are caused.

I learn many subjects in school. But the one I enjoy learning is History.

History tells us how people lived ages ago. It also tells us how men had to struggle to make the world a better place to live. Many pupils, however, do not to read History. They say that there are too many names and dates to remember. But they do not understand that if we do not know about the past, we can not understand the present properly. In fact, only a study of History will make us realize that everything we do today is the result of what our grandfathers and others before them did in the past. So, History is the long story, we learn many interesting things.

I love history so much that i have a lot of history books in my house. Some day, i might even write a history book myself.

When going to school, there are many subjects; however I still literature the most. First, literature plays an important role in both education and daily life. Literature is not limit to a subject to be learnt at school. Furthermore, this subject teaches human about several aspects of life. From the very first step, student learns to write, read as well as describe things and people. Moreover, literature teaches one to be a responsible citizen and able personality. Literature is more than a subject, it’s an art and it can be applied directly into life such as: journalism, writing skill. People are not born to learn this unique subject, it needs long time to exercise to master. Besides, when learning literature people not only know more works of art but also understand culture, tradition of each country. Literature is the mirror reflecting human and their lifestyle. Studying literature means learning the way to love and live a true life. All in all, with great benefits of literature, it is necessary for each society especially developing countries.

a)Đặt A=1 + 6 + 11 + 16 +...+ 46 + 51

Tổng A có số số hạng là:

(51-1):5+1=11 (số)

Tổng A là:

(51+1)*11:2=286

a)Số số hạng của tổng là:

 ( 51 - 1) : 5 + 1 = 11

Tổng là :

( 51 + 1 ) : 2 x 11 = 286

                           Đ/s : 286

Còn câu b mk ko biết làm,xin lỗi nha

 1 + 6 + 11 + 16 +...+ 46 + 51

Ta áp dụng công thức có :

SSH : ( 51 - 1 ) : 5 + 1 = 11 

Tổng dãy : ( 51 + 1 ) . 11 : 2 = 286

CHÚC BẠN HỌC TỐT !!!

cách 1:\(\frac{2^5.9^2}{6^4.8}=\frac{32.81}{1296.8}=\frac{1}{4}\)

cách 2 tách 2^5 và 9^2 mẫu tương tự

cách 1:\(\frac{2^5.9^2}{6^4.8}=\frac{32.81}{1296.8}=\frac{1}{4}\)

cách 2 tách 2^5 và 9^2 mẫu tương tự

\(\frac{2^5.9^2}{6^4.8}=\frac{2^5.\left(3^2\right)^2}{2^4.3^4.2^3}=\frac{2^5.3^4}{2^7.3^4}=\frac{1}{2^2}=\frac{1}{4}\)

1 unimportant

2 unkind

3 unpopular

4impossible

5 unhappy

6 fasten

7 competition

8 athlete

9 unsuccessful

10 sportmanship

11 delegate

12 warmthly

13quickly

14 amazed

15 carelessly

16 beautifully

17 regularly

18 cooperation

19 pollution

20 expectation

21 protection

22 performance

23 product

24 education

25 thrilling

26 pollution

27 gently

28 happily

29 polluted

30 successfully

31 preparation

32 boring

33 collection

34 similarities

35 amusing

36 accidentally

37 decision

38 weakness

39 unforgetable 

40 impatience

41 careless

42 competitors

43 addiction

44 lengthened

45 unidentified

46 unfashionable 

47 preventing - prevention

48 singer

49 musical

50 children

hơi bị nhiều ;-;

e có thể chia bài ra đc chứ, e cũng biết là hơi bị nhiều mà

= 1 - 1/2 + 1/2 - 1/4 + 1/4 - 1/8 + ...... + 1/512 - 1/1024

=1 - 1/1024

=1023/1024

k nha