1×2/1+2×3/1+3×5/1+5×7/1﹢…﹢97×99/1+99×101/1
=(1-2/1)+(2/1-3/1)+.+(97/1-99/1)+(99/1-101/1)
=1-101/1
=101/100对不起出错题了 1×3/1+3×5/1+5×7/1﹢…﹢97×99/1+99×101/11×3/1+3×5/1+5×7/1﹢…﹢97×99/1+99×101/1=2/1(1-3/1)+2/1(3/1-5/1)+。。。+2/1(97/1-99/1)+(99/1-101/1)=2/1(1-101/1)=101/50