1/(n+6)(n+7)+1/(n+7)(n+8)+1/(n+8)(n+9)+1/(n+9)(n+10)=_数学解答

1/(n+6)(n+7)+1/(n+7)(n+8)+1/(n+8)(n+9)+1/(n+9)(n+10)=

人气：204 ℃　时间：2020-10-01 15:06:12

解答

=1/(n+6)-1/(n+7)+1/(n+7)-1/(n+8)+1/(n+8)-1/(n+9)+1/(n+9)-1/(n+10)
=1/(n+6)-1/(n+10)
=4/(n+6)(n+10)