1/m(m+1)+1/(m+1)(m+2)+1/(m+2)(m+3)+.+1/(m+9)(m+10)

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/20 06:36:24
1/m(m+1)+1/(m+1)(m+2)+1/(m+2)(m+3)+.+1/(m+9)(m+10)
x)366@1q5 \K@&Hmv6dcL-5B"y`PUFEP{`!u6<ٽi{R4&lT. LL!J~qAb(b

1/m(m+1)+1/(m+1)(m+2)+1/(m+2)(m+3)+.+1/(m+9)(m+10)
1/m(m+1)+1/(m+1)(m+2)+1/(m+2)(m+3)+.+1/(m+9)(m+10)

1/m(m+1)+1/(m+1)(m+2)+1/(m+2)(m+3)+.+1/(m+9)(m+10)
∵ 1/m(m+1) = 1/m - 1/(m+1),
1/(m+1)(m+2) = 1/(m+1) - 1/(m+2)
1/(m+2)(m+3) = 1/(m+2) - 1/(m+3)
所以原式 = 1/m - 1/(m+1) + 1/(m+1) - 1/(m+2) + 1/(m+2) - 1/(m+3) ...+ 1/(m+9) - 1/(m+10)
= 1 - 1/(m+10)
= (m+9)/(m+10)