Các câu hỏi tương tự
TÍnh nhanh: 1/2x(1+2) + 1/2x(1+2+3) + 1/2x(1+2+3+4) + ... + 1/2x(1+2+3+4+5+6+7+8+9)
Tính nhanh :
1 + 7 + 8 + 15 + 23 + ... + 160
1 + 4 + 5 + 9 + 14 + ... + 60 + 97
A = 1 x 4 + 2x 5 + 3 X 6 + 4 x 7 + ... + n x ( n + 3 )
5 9/10 : 3/2-[ 2 1/3x 4 1/2-2x 2 1/3 ] :7/4
1. 4 1/7 - x = 2 5/9
2. 3 × x = 12,18
3. 4 1/2 × x = 5
4. 3/4 × x = 1
5. 4/5 : x = 3
6. 12/x = 4
7. 4/7 : x = 4/7
8. 2x - 3/4 = 7/8
P/s : Giúp mk nha mấy bạn 😘😘
18x(19191919/21212121+88888/99999 va 4 2/5+1/3+5 6/9+1/4+2 3/4+2/5 va (5/111111+5/222222-4/3x7x11x13x37)x10101 va 1/2x 2/3x 3/4x 4/5x 5/6x 6/7x 7/8x 8/9x 9/10 va 7/4x (3333/1212 +3333/2020 +3333/3030 +3333/4242)
1/2x +( 2/4+3/6)= 4/5
3/8+x=2/5
4x-x = 2+13
3x+x = 1/4
x-0,5x = 4
x- 0,25x = 1
4x- 3/4x + 5 =
3x - x - 7 = 1+x
8x + 2x + 20 = 25- 2x
3 - 1/2x = x - 1
5x - x + 15 = x + 40
6 + x = 22/3 + 2 - x
1/x-1+-2/3(3/4-6/5)=5/2-2x
1/1+2+1/1+2+3+1/1+2+3+4.......+1/1=2+3+4+5+6+7+8+9+10
tính nhanh