1/1*2+1/2*3+1/34+1/4*5+1/5*6
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6
=1-1/6
=5/6
Bài này là toán lớp 6 mà
1/1*2+1/2*3+1/34+1/4*5+1/5*6
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6
=1-1/6
=5/6
Bài này là toán lớp 6 mà
Tinh nhanh : a)2 1/3 + 4 1/5 + 4 1/3
b)5 3/4 - 4 1/2 * 3 7/8
c)1 1/2 * 3 2/3 * 4 3/4
d)6 4/5 : 2 3/4 : 1 1/2
tinh nhanh :1\2*3+1\3*4+1\4*5+1\5*6
Tinh bang cach thuan tien nhat:
a) 1/3 + 1/4 + 2/3 + 3/4
b) 1/2 + 1/3 - 1/5 + 1/6
c) 2/3 x 4/5 + 1/3 x 4/5
d) 2/3 x 4/5 - 1/3 x 4/5
A= 1/2*3 + 1/3*4 + 1/4*5 +1/5*6 +1/6*7 +1/7*8
tinh nhanh
Tinh nhanh
A=1/1*2+1/2*3+1/3*4+1/4*5+1/5*6+1/6*7+1/7*8+1/8*9+1/9*10
Tinh Nhanh:
6 2/7 + 7 3/5 + 8 6/9 + 9 1/4 +2/5 + 5/7 + 1/3 + 3/4 + 1967
Tinh bang cach thuan tien nhat :
a) 1/3 + 1/4 + 2/3 + 3/4
b) 1/2 + 1/3 - 1/5 + 1/6
tinh nhanh
A = 1/(1+2) + 1/(1+2+3).....+ 1/(1+2+3+4+5+6+7+8+9+10)
Tinh nhanh
A. 1 1/3:1 1/4:1 1/5:1 1/6
B. 2/3*1/6*9/11