2n+1 chia hết cho n-3

=>2n-6+7 chia hết cho n-3

mà 2n-6 chia hết cho n-3

=>7 chia hết cho n-3

=> n-3 E Ư(7)

n-3={-7;-1;1;7}

hide- and seek

How to play:
The number of children is between 8 and 10 children. Games can be held in the yard or in the classroom. Before playing the children together to agree on the range of where to hide. If someone hides outside the scope of the agreement, the person must seek will not seek. At the beginning of the game, the game's leader gathers the players in a circle. He stretched out his hand. Each member placed a forefinger in the hands of the leader, and the group read the knife together, "each with a finger. The knife is as follows:
Spend your time
The fire blows
The horse is dead
Three Kings
Get the crickets to find
Unhappy
To the sentence "ù à ù ũ", the captain quickly clenched his hands, everyone must quickly pull out. One who does not pull his hand out, the leader who catches that person must be blindfolded as "seek", and others will flee within the agreed range. The blindfold begins to count: "5 -10 -15- 20 -25 -30 -35-40- 45- 50- 55- 60-65-70-75 -80-85-90-95 -100", at The blindfolders are beginning to count, it is also the time people go to hide the hurry to run away to find shelter, if he closed his eyes counted to 100, but someone who fled or did not find shelter. Being "caught" to "find". If the searcher has found enough members, then start the new game, the first finder will have to be "blindfolded to find", and if there are 1 to 2 members have not found the search. Speak loudly ", then those who flee happily go out of the hide. The seeker must blindfold and look again at the next game, so the game continues ...
* Attention:
In this "hide and seek" game, the final fugitive is the leader, because he must also blindfold and investigate the sincerity of the seeker.
Game members must strictly follow the rules of the game, ie to escape within the limits agreed upon by the player at the start of the game; if they hide in other places, the blind will not find them; or the blindfolder must be honest, do not peek at those who escape.

Số số hạng của dãy là : 50 - 1 + 1 = 50 (số)

Tổng của dãy là : (50 + 1) * 50 / 2 = 1275 

CÓ 4 CON 

TICK CHO MIK NHA CẦU XIN BẠN ĐÓ

bàn tay

bàn chân 

-1539756

hic.....mỏi tay quá .

\(\frac{2}{5}=\frac{4}{10}=\frac{8}{20}\)

nhưng tôi chỉ tính S thôi còn tìm GTLN thì bn tự tìm nhé

The number of children is between 8 and 10 children. Games can be held in the yard or in the classroom. Before playing the children together to agree on the range of where to hide. If someone hides outside the scope of the agreement, the person must seek will not seek. At the beginning of the game, the game's leader gathers the players in a circle. He stretched out his hand. Each member placed a forefinger in the hands of the leader, and the group read the knife together, "each with a finger. The knife is as follows:
Spend your time
The fire blows
The horse is dead
Three Kings
Get the crickets to find
Unhappy
To the sentence "ù à ù ũ", the captain quickly clenched his hands, everyone must quickly pull out. One who does not pull his hand out, the leader who catches that person must be blindfolded as "seek", and others will flee within the agreed range. The blindfold begins to count: "5 -10 -15- 20 -25 -30 -35-40- 45- 50- 55- 60-65-70-75 -80-85-90-95 -100", at The blindfolders are beginning to count, it is also the time people go to hide the hurry to run away to find shelter, if he closed his eyes counted to 100, but someone who fled or did not find shelter. Being "caught" to "find". If the searcher has found enough members, then start the new game, the first finder will have to be "blindfolded to find", and if there are 1 to 2 members have not found the search. Speak loudly ", then those who flee happily go out of the hide. The seeker must blindfold and look again at the next game, so the game continues ...
* Attention:
In this "hide and seek" game, the final fugitive is the leader, because he must also blindfold and investigate the sincerity of the seeker.
Game members must strictly follow the rules of the game, ie to escape within the limits agreed upon by the player at the start of the game; if they hide in other places, the blind will not find them; or the blindfolder must be honest, do not peek at those who escape.

Đoạn thơ diễn tả cảm xúc vui mừng khôn xiết của gia đình sau nhiều ngày mong ngóng mẹ về. Mẹ đi vắng, cũng là lúc cơn bão ập đến. Cơn bão của thiên nhiên hay cơn bão trong lòng mỗi người khi không có mẹ? Mẹ trở về, thời gian xa vắng đã kết thúc, giống như cơn bão đã tan, trời lại quang mây, lặng gió. Người mẹ được tác giả so sánh như “nắng mới” trở lại, làm cho gian nhà ẩm ướt sau cơn bão như “sáng ấm” lên. Hình ảnh “nắng mới” là hình ảnh của mẹ, mẹ đã trở về xua đi sự trống trải, sự mong mỏi của mọi người trong gia đình.