1/(12*13)+1/(13*14)+1/(14*15)+1/(15*16)+1/(16*17)+1/(17*18)+
来源:学生作业帮 编辑:搜搜考试网作业帮 分类:数学作业 时间:2024/05/13 14:15:28
1/(12*13)+1/(13*14)+1/(14*15)+1/(15*16)+1/(16*17)+1/(17*18)+1/(18*19)+1/(19*20)=?
1/a(a+1)=1/a-1/(a+1)
1/(12*13)+1/(13*14)+1/(14*15)+1/(15*16)+1/(16*17)+1/(17*18)+1/(18*19)+1/(19*20)
=1/12-1/13+1/13-1/14+1/14-1/15+……+1/19-1/12
=1/12-1/20
=5/60-3/60
=2/60
=1/15
1/(12*13)+1/(13*14)+1/(14*15)+1/(15*16)+1/(16*17)+1/(17*18)+1/(18*19)+1/(19*20)
=1/12-1/13+1/13-1/14+1/14-1/15+……+1/19-1/12
=1/12-1/20
=5/60-3/60
=2/60
=1/15
1/(12*13)+1/(13*14)+1/(14*15)+1/(15*16)+1/(16*17)+1/(17*18)+
(1-12)(1-13)(1-14)(1-15)(1-16)(1-17)(1-18)(1-19)0.1+0.2+0.3+
A=1\10+1\11+1\12+1\13+1\+1\14+1\15+1\16+1\17+1\18+1\19分之1 求A
1 2 4 5 6 9 10 12 13 14 15 16 17 18 20 21
1/1/10 1/11 1/12 1/13 1/14 1/15 1/16 1/17 1/18 1/19化简后整数部分是多
求1/10+1/11+1/12+1/13+1/14+1/15+1/16+1/17+1/18+1/19的整数部分【听不懂哈
1/11+1/12+1/13+1/14+1/15+1/16+1/17+1/18+1/19+1/20=?
求1/10+1/11+1/12+1/13+1/14+1/15+1/16+1/17+1/18+1/19的整数部分?
1/14*15+1/15*16+1/16*17+1/17*18
将1/5+1/6++1/8+1/9+1/10+1/11+1/12+1/13+1/14+1/15+1/16+1/17的计算
|1\12-1\11|+|3\13-1\12|+1\14-1\13|+|1\15-1\14|+||1\16-1\15|
20+19-18+17+16+15-14-13+……+4+3-2-1