X
xphongx
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
1) 1/1.2 + 1/2.3 + 1/3.4 +...+ 1/2012.2013
2) 1/100.99 - 1/99.98 - 1/98.97 -...- 1/3.2 - 1/2.1
3)-1/2013.2012 - 1/2012.2011 - 1/2011.2010 -...- 1/3.2 - 1/2.1
4) 3/2.5 + 3/5.8 +...+ 3/(3n-1)(3n+2)
5) 2/1.2.3 + 2/2.3.4 + 2/3.4.5 +...+ 2/n(n+1)(n+2)
6) (1/2 - 1)(1/3 - 1)(1/4 - 1)...(1/2012 - 1) (mấy phân số đó trừ cho 1)
7)-1 1/2.(-1 1/3).(-1 1/4)...(-1 1/2013)
8)1/1.4 + 1/4.7 + 1/7.10 +...+ 1/100.103
9) (1/2 - 1)(1/3 - 1)...(1/10 - 1) ((mấy phân số đó trừ cho 1)
10)(1 - 1/21).(1 - 1/28).(1 - 1/36)...(1 - 1/1326) (1 trừ cho mấy phân số)
11)(1 - 1/1.3).(1+1/2.4).(1+1/3.5)...(1 + 1/99.101)
12) 3/4 . 8/9 . 15/16 ... 9999/10000
13) 2^100 - 2^99 + 2^98 - 2^97 +...+ 2^2 - 2
Nhờ mọi người giải giúp với![Frown :( :(](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
2) 1/100.99 - 1/99.98 - 1/98.97 -...- 1/3.2 - 1/2.1
3)-1/2013.2012 - 1/2012.2011 - 1/2011.2010 -...- 1/3.2 - 1/2.1
4) 3/2.5 + 3/5.8 +...+ 3/(3n-1)(3n+2)
5) 2/1.2.3 + 2/2.3.4 + 2/3.4.5 +...+ 2/n(n+1)(n+2)
6) (1/2 - 1)(1/3 - 1)(1/4 - 1)...(1/2012 - 1) (mấy phân số đó trừ cho 1)
7)-1 1/2.(-1 1/3).(-1 1/4)...(-1 1/2013)
8)1/1.4 + 1/4.7 + 1/7.10 +...+ 1/100.103
9) (1/2 - 1)(1/3 - 1)...(1/10 - 1) ((mấy phân số đó trừ cho 1)
10)(1 - 1/21).(1 - 1/28).(1 - 1/36)...(1 - 1/1326) (1 trừ cho mấy phân số)
11)(1 - 1/1.3).(1+1/2.4).(1+1/3.5)...(1 + 1/99.101)
12) 3/4 . 8/9 . 15/16 ... 9999/10000
13) 2^100 - 2^99 + 2^98 - 2^97 +...+ 2^2 - 2
Nhờ mọi người giải giúp với
Last edited by a moderator: