< 1/2 + 1/3 + 1/4 + ...1/60> + < 2/3 + 2/4 + 2/5 + ...+ 2/60>+< 3/4 + 3/5 + ...+ 3/60> + ...+ < 58/59 + 58/60 > + 59/60=?
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/24 11:35:13
![< 1/2 + 1/3 + 1/4 + ...1/60> + < 2/3 + 2/4 + 2/5 + ...+ 2/60>+< 3/4 + 3/5 + ...+ 3/60> + ...+ < 58/59 + 58/60 > + 59/60=?](/uploads/image/z/5545069-61-9.jpg?t=%3C+1%2F2+%2B+1%2F3+%2B+1%2F4+%2B+...1%2F60%3E+%2B+%3C+2%2F3+%2B+2%2F4+%2B+2%2F5+%2B+...%2B+2%2F60%3E%2B%3C+3%2F4+%2B+3%2F5+%2B+...%2B+3%2F60%3E+%2B+...%2B+%3C+58%2F59+%2B+58%2F60+%3E+%2B+59%2F60%3D%3F)
< 1/2 + 1/3 + 1/4 + ...1/60> + < 2/3 + 2/4 + 2/5 + ...+ 2/60>+< 3/4 + 3/5 + ...+ 3/60> + ...+ < 58/59 + 58/60 > + 59/60=?
< 1/2 + 1/3 + 1/4 + ...1/60> + < 2/3 + 2/4 + 2/5 + ...+ 2/60>+< 3/4 + 3/5 + ...+ 3/60> + ...+ < 58/59 + 58/60 > + 59/60=?
< 1/2 + 1/3 + 1/4 + ...1/60> + < 2/3 + 2/4 + 2/5 + ...+ 2/60>+< 3/4 + 3/5 + ...+ 3/60> + ...+ < 58/59 + 58/60 > + 59/60=?
直接把括号打开,再组合得到:1/2+(1/3+2/3)+(1/4+2/4+3/4)+...+(1/59+2/59+...+58/59)+(1/60+...+59/60)=0.5+1+1.5+2+2.5+...+29.5=29*30+15=885