A=10/56+10/140+10/260+......+10/1400
tính A=10/56 +10/140 + 10/260 +............ + 10/1400
H = 10/56+10/140+10/260+10/1400
10/56+10/140+10/260+.....+10/1400
Tính tổng:A=10/56+10/140+10/260+.........+10/1400
10/56+10/140+10/260+...+10/1400
Tính tổng A=10\56+10\140+10\260+..+10\1400
10/56 + 10/140 + 10/260 + ...+ 10/1400
tính: 10/56+10/140+10/260+...+10/1400