1/6+1/12+1/20+1/30.....+1/2005*2006等于多少
来源:百度知道 编辑:UC知道 时间:2024/05/28 14:09:10
1/6+1/12+1/20+1/30.....+1/2005*2006
=1/(2*3)+1/(3*4)+...+1/(2005*2006)
=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+...+(1/2005-1/2006)
=1/2-1/2006
=自己化简~~:)
这个题目的没一项都为1/n*(n+1)
1/n*(n+1)=1/n-1/(n+1)
所以上题为1/2-1/3+1/3-1/4…………+1/2005-1/2006=1/2-1/2006=501/1003
这个用数列算啊
1+1/3+1/6+........+1/55
5/6=1/?+1/?+1/?
1/2+1/6+1/12+1/20+1/30
1/6+1/8+1/10+1/12+..........+1/202=?
1/2+1/4+1/6+1/8+.......+1/n=?
-1/2-1/6-1/12-1/20-``````````````-1/4026042
1/2+1/6+1/12+......+1/1980+1/2070=?
(1/2) (1/4+1/6)=
(1/2-1)*(1/3-1)*(1/4-1)*(1/5-1)*(1/6-1)*(1/7-1)*(1/8-1)*(1/9-1)*(1/10-1)
1/2 ,1/3 ,1/6 /1/6 ,()