因为绝对值里面的值都是正数！所以是它本身！
|1/3-1/4|+|1/4-1/5|+……+|1/19-1/20|
＝1/3-1/4+1/4-1/5+……+1/19-1/20
＝1/3-1/20
＝17/60本回答被提问者采纳
=1/(2*3)+1/(4*5)+1/(6*7)+1/(8*9)+1/(10*11)+1/12
=1/6+1/20+1/42+1/72+1/110+1/12
=1/6+1/12+1/20+1/42+1/72+1/110
=468304/443520
=29269/27720
好像是我算错了，你再按按计算器，这题没这么难吧……
总之是 1/n-1/(n+1)=1/n(n+1)
1+1\/2-1\/3+1\/4-1\/5+1\/6-1\/7+1\/8-1\/9+1\/10-1\/11+1\/12 等于多少 要分数的...
原式=1+1\/2+1\/4+1\/6+1\/8+1\/10+1\/12 -1\/3-1\/7-1\/9-1\/11 =1+(6+3+2+1)\/12+(5+4)\/40 -(3+1)\/9-(11+7)\/77 =1+1+9\/40-4\/9-18\/77 =9\/40+5\/9+59\/77 =(9×9×77+5×40×77+59×40×5)\/(360×77)=33437\/27720 =1+5717\/27720 ...
...1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10+1\/11+1\/12+1\/13)×2004计算...
2004能被2，3，4，6，12整除，所以可以不考虑1\/2，1\/3，1\/4，1\/6，1\/12 2004除以5，8，10是有限小数，所以也可以不考虑1\/5，1\/8，1\/10 2004\/7=286.285714285714，是一个6位的循环，小数点后第2004位，2005位是42 2004\/9=222，666是一个1位的循环，小数点后第2004位，2005位是66 2...
1-1\/2+1\/3-1\/4+1\/5-1\/6+1\/7-1\/8+1\/9-1\/10+1\/11-1\/12
一就是淡定慢慢算，，可以求数列1\/n的和与1\/2n的和作差吧
...1\/4+1\/6-1\/5+1\/7-1\/6+1\/8-1\/7+1\/9-1\/8+1\/10-1\/9=?
原式 = 1 + 1\/3 + 1\/4 + 1\/5 + 1\/6 + 1\/7 + 1\/8 + 1\/9 + 1\/10 - 1\/2 - 1\/3 - 1\/4 - 1\/5 - 1\/6 - 1\/7 - 1\/8 - 1\/9 = 1 + 1\/10 - 1\/2 = 1\/2 + 1\/10 = 3\/5 希望对你有帮助，新年快乐~...
1+1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10=多少
计算1+1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10的过程如下：首先，我们可以通过拆分求和的方法简化计算：= 1 + (1\/2 + 1\/3 + 1\/6) + (1\/4 + 1\/5 + 1\/10) + 1\/7 + 1\/8 + 1\/9 = 1 + 1 + (1\/2 + 1\/3 - 1\/6) + (1\/4 + 1\/5 + 1\/10)= 1 +...
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10等于多少?
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10 =(1\/2+1\/3+1\/6)+(1\/4+1\/5+1\/10)+1\/7+1\/8+1\/9 =1+11\/20+1\/8+1\/7+1\/9 =1+27\/40+1\/9+1\/7 =1+283\/360+1\/7 =1+2341\/2520 =4861\/2520
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10+...1\/100这道题怎样简算_百度知 ...
很早就有数学家研究，比如中世纪后期的数学家Oresme在1360年就证明了这个级数是发散的。他的方法很简单： 1 +1\/2+1\/3 +1\/4 + 1\/5+ 1\/6+1\/7+1\/8 +... 1\/2+1\/2+(1\/4+1\/4)+(1\/8+1\/8+1\/8+1\/8)+... 注意后一个级数每一项对应的分数都小于调和级数中每一项，而且后面级数...
1\/2-1\/3+1\/4-1\/5+1\/6-1\/7+1\/8.计算有什么规律没有,
如果是选择题,且各选项中的分数都没有约过分的话,分母一定是n的阶层（n!=1*2*3*...*n）.例如,1\/2-1\/3+1\/4-1\/5=(4*5-2*3)\/2*3*4*5;1\/6-1\/7+1\/8-1\/9=(8*9-6*7)\/6*7*8*9;则1\/2-1\/3+1\/4-1\/5+1\/6-1\/7+1\/8-1\/9=[(4*5-2*3)*...
求助一道数学题:1-1\/2+1\/3-1\/4+1\/5-1\/6+1\/7-1\/8+1\/9……+1\/19-1\/20...
1-1\/2+1\/3-1\/4+...+1\/19-1\/20=(1-1\/2+1\/3-1\/4+1\/5-1\/6+1\/7-1\/8+1\/9-1\/10)-(1\/12+1\/14+1\/16+1\/18+1\/20)+(1\/11+1\/13+1\/15+1\/17+1\/19)=1\/11+(1\/3-1\/6-1\/12)+1\/13+(1\/7-1\/14)+1\/15+(1-1\/2-1\/4-1\/8-1\/16)+1\/17+(1\/9-1\/18)+...
数学题1\/3-1\/2的绝对值+1\/4-1\/3的绝对值+1\/5-1\/4的绝对值+。。。1\/...
每个绝对值里都是小的减去大的，所以绝对值之后就等于大的减小的。则该式子可以简化为1\/2-1\/3 + 1\/3-1\/4 + 1\/4-1\/5 +1\/5-1\/6 +1\/6-1\/7 + 1\/7-1\/8 +1\/8-1\/9 + 1\/9-1\/ 整理后，正好得到1\/2-1\/10=5\/10-1\/10=4\/10=2\/5，所以答案就是2\/5 ...
