3/(2*5)+3/(5*8)+3/(8*11)+……+3/(1994*1997*)1又1/(3*5)+2又1/(5*7)+3又/(7*9)+……+100又1/(201*203)1/(1*3)+1/(3*5)+1/(5*7)+……+1/(97*99)+1/(99*101)我已经会了你做错了

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/13 11:43:07

3/(2*5)+3/(5*8)+3/(8*11)+……+3/(1994*1997*)1又1/(3*5)+2又1/(5*7)+3又/(7*9)+……+100又1/(201*203)1/(1*3)+1/(3*5)+1/(5*7)+……+1/(97*99)+1/(99*101)我已经会了你做错了
3/(2*5)+3/(5*8)+3/(8*11)+……+3/(1994*1997*)
1又1/(3*5)+2又1/(5*7)+3又/(7*9)+……+100又1/(201*203)
1/(1*3)+1/(3*5)+1/(5*7)+……+1/(97*99)+1/(99*101)
我已经会了
你做错了

3/(2*5)+3/(5*8)+3/(8*11)+……+3/(1994*1997*)1又1/(3*5)+2又1/(5*7)+3又/(7*9)+……+100又1/(201*203)1/(1*3)+1/(3*5)+1/(5*7)+……+1/(97*99)+1/(99*101)我已经会了你做错了
第一个
=1/2-1/5+1/5-1/8+1/8-1/11……-1/1997
=665/1332
第二个
=1+2+3.+100+(1-1/3+1/3-1/5.-1/203)/2
=5050又101/203
第三个和第二个后面一样