来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/11/14 06:58:23
是计算题我打不出题目见谅
1/(1×3)+1/(3×5)+1/(5×7)+1/(7×9)+...+1/(49×51)
=(1-1/3)×1/2+(1/3-1/5)×1/2+(1/5-1/7)×1/2+(1/7-1/9)×1/2+...+(1/49-1/51)×1/2
=(1-1/3+1/3-1/5+1/5-1/7+1/7-1/9+...+1/49-1/51)×1/2
=(1-1/51)×1/2
=50/51×1/2
=25/51