ra 0 chuẩn 100% ai k mình , mình tích lại gấp đôi
ra 0 chuẩn 100% ai k mình , mình tích lại gấp đôi
1+2+3+4+5+6+7+8+9+1+2+3+4+5+6+7+8+9+1+2+3+4+5+6+7+8+9=?
1+1+1+2+2+2+3+3+3+4+4+4+5+5+5+6+6+6+7+7+7+8+8+8+9+9+9+.......+n
Tìm n
Tính nhanh: A) 4/9+1/8+5/9+7/8 B) 1/6+4/6+5/12+7/6+7/12
a) 60 × (7/12 + 4/15) =
b) 5/6 ×( 6/5 - 6/7 ) =
c) 1/2 × 2/3 × 3/4 × 4/5 × 5/6× 6/7 × 7/8 × 8/9 =
1+1+1+1+1+2+3+4+5+6+7+8+9+10 x 1+1+1+1+1+2+3+4+5+6+7+8+9+10 +1+1+1+1+1+2+3+4+5+6+7+8+9+10 - 10 x 9 - 9 + 45 +46 +47 =
1+9+3+7+5+8+4+6+2+1+2+3+4+5+7+8+6+9=maays
5/6 + 5/8 + 3/4
12/15 + 3 + 3/5
4/3 x 7/8 x 5
8/9 x 6/5 : 3
7/12 + 5/8 x 4/3 - 3/4
(8/5 - 7/6) : 13/15 + 1/4
tinh nhanh 1/4*3+1/4*5+1/6*5+1/7*6+1/8*7+1/9*8+1/10*9=
bài 1:
a,1/10*2/9*3/8*4/7*5/6*6/5*7/4*8/3*9/2
b,8/11+4/17-5/11-3/17-65/9-8/17-3/17-6/17