Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
M= 1 - 1/2 + 1/2 - 1/3 +1/3 -1 /4 + 1/4 - 1/5 + .....+ 1/10 - 1/11 + 1/11 -1/12
= 1 - 1/12
= 11/12
3 k lun
a, với n thuộc Z
Để A là một số nguyên thì 3n + 1 chia hết cho n+1
mà n + 1 chia hết n +1
=> (3n+1) - 3. (n+1) chia hết cho n+1
<=> (3n+1)-( 3n +3) chia hết cho n+1
<=> 4 chia hết cho n+1
=> n+1 thuộc Ư(4)= {+-1; +-4; +-2}
nếu ............
Câu a:
A = \(\frac{3n+1}{n+1}\)
A ∈ Z khi và chỉ khi:
(3n + 1) ⋮ (n + 1)
[3(n + 1) - 2] ⋮ (n + 1)
2 ⋮ (n + 1)
(n + 1) ∈ Ư(2) = {-2; -1 ; 1; 2}
n ∈ {-3; - 2; 0; 1}
Vậy n ∈ {-3; - 2; 0; 1}
bạn ơi mình nghĩ bạn hãy đưa qua mục toán đi ạ sẽ có nhiều người giỏi trả lời hơn
Lesson 1: A school with 1200 students. The number of students with average academic performance is 5858, total number of students is 1313, the rest are good students. Calculate the number of students in this school.
Lesson 2: A rectangular garden of length 14121412 m, width 3535 in length. Calculation of the perimeter and area of the garden.
Lesson 3: A team of workers must plant 3 crops. In the first stage, 1313 plants were planted. The second crop 3737 planted the remaining trees. Session 3 planted 160 plants. Calculates the total number of trees the team must plant.
Exercise 4: Give two circles (O; 4cm) and (O '; 2cm) such that the distance between two centers O and O' is 5cm. Circle O (O; 4cm) cut OO 'at point A and circle O (O 2) cut OO at B.
A, Calculate O'A, BO, AB
B, Prove that A is the midpoint of the segment O'B?
Lesson 5: When paying for a book at the right price; Hung is refunded 15,000 VND, because of the 105% promotion. So how much did Hung buy that book?
1. _______blood_______ noun something natural that happens in the body.
2. ______lung________ noun two parts indide the top half of your body that you use to breath.
3. ______pump________ verb to make a liquid move to another placeby pushing it.
4. _______heart_______ noun the part inside your chest that makes blood go around your body.