1+(1+2)分之1+(1+2+3)分之1+.........+(1+2+3+.......100)分之1
聪明人加油
参考答案:(1+2+...+n)分之1
=2/[n(n+1)]
=2*(1/n-1/(n+1))
1+(1+2)分之1+(1+2+3)分之1+.........+(1+2+3+.......100)分之1
=2*(1-1/2+1/2-1/3+...+1/100-1/101)
=2*(1-1/101)
=200/101
聪明人加油
参考答案:(1+2+...+n)分之1
=2/[n(n+1)]
=2*(1/n-1/(n+1))
1+(1+2)分之1+(1+2+3)分之1+.........+(1+2+3+.......100)分之1
=2*(1-1/2+1/2-1/3+...+1/100-1/101)
=2*(1-1/101)
=200/101