1/2+5/6+11/12+...111221/111222

来源:百度知道 编辑:UC知道 时间:2024/05/26 05:00:06
1/2+5/6+11/12+...+111221/111222=

原式=1-1/2+1-1/6+1-1/12+...+1-1/111222
=(1+1+1+...+1)(333个)-(1/2+1/6+1/12+...+1/111222)
=333-1/(1*2)-1/(2*3)-1/(3*4)+...-1/(333*334)
=333-(1-1/2+1/2-1/3+1/3-1/4+...+1/333-1/334)
=333-(1-1/334)
=332+1/334
=110889/334

裂项
原式=333-(1/2+1/6+1/12+...+1/111222)=333-(1-1/2+1/2-1/3+1/3-1/4+...+1/333-1/334)=333-333/334=332又1/334

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