(1/2+1/3+1/4+…+1/60)+(2/3+2/4+2/5…+2/60)+(3/4+3/5+…+3/60)+…+
(1+1/2+1/3+……+1/60)+(2/3+2/4+……+3/60)+……+(58/59+58/60)+1/60
(1/2+1/3+1/4+…+1/59+1/60)+(2/3+2/4+2/5+…+2/59+2/60)+(3/4+3/5
(1/2+1/3+1/4+…+1/60)+(2/3+2/4+2/5…+2/60)+(3/4+3/5+…+3/60)+…+
(1/2+1/3+1/4+……+1/60)+(2/3+2/4+2/5+……+2/60)+……+(58/59+58/60)
1/2+1/3+2/3+1/4+2/4+3/4+1/5+……+1/60+2/60+……+59/60
1/2+(1/3+2/3)+(1/4+2/4+3/4)+…+(1/60+2/60+…58/60+59/60)简便算法
1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+……+(1/60+2/60+
计算:1/2+1/3+2/3+1/4+2/4+3/4+1/5+2/5+3/5+4/5+……+1/6+…+59/60
求和:1-2+3-4+5………+(2n-1)-2n=
(1+1/2+1/3+...+1/60)+(2/3+2/4+...+2/60)+(3/4+3/5+...+3/60)+.
六年级奥数题(1/2+1/3+1/4+…+1/15)+(2/3+2/4+…+2/15)+(3/4+3/5+…+3/15)
(1+3+5……+2009)-(2+4+6+……+2010)=?