1/1×3+1/3×5+1/5×7+...+1/99×101=?

1*1/3+3*1/5+5*1/7+.+97*1/99+99*1/101= 1/(1+3)+1/(3+5)+1/(5+7)…+1/(99+101)=( )简便计算 1×(1/3)+3×(1/5)+5×(1/7)+...+99×(1/101)=多少? 简算:1/(1*3)+1/(3*5)+1/(5*7)+……+1/(99*101)= 1/1*3+1/3*5+1/5*7+...+1/99*101=?为什么 1/1×3+1/3×5+1/5×7+...+1/99×101=? 1/1*3+1/3*5+1/5*7+...+1/99*101=?(要简便) 解数学题1/1*3+1/3*5+1/3*7+...+1/99*101=? 1/(1×3)+1/(3×5)+1/(5×7).+1/(97×99)+1/(99×101) 帮帮忙1/1*3+1/3*5+1/5*7+1/7*9+...1/99*101 计算:1/1*3+3/3*5+5/5*7+...+99/99*101为什么要=1/2*[(1-1/3)+(1/3-1/5 1.计算：1/1*3+1/3*5+1/5*7+……+1/99*101