巧算:1×(1-1/2)×(1-1/3)×……×(1-1/2005)×(1-1/2006)×(1-1/2007)×(1-
巧算:1×(1-1/2)×(1-1/3)×……×(1-1/2005)×(1-1/2006)×(1-1/2007)×(1-
巧算1/2*1/3+1/3*1/4+1/4*1/5+……+1/2006*1/2007+1/2007*1/2008
计算:(1/2006-1)(1/2005-1)(1/2004)… (1/3-1)(1/2-1).
计算:| 1/2008-1/2007 |+| 1/2007-1/2006 |+| 1/2006-1/2005 |+……+
1+1/2+1/3+1/4+……+1/2004+1/2005+1/2006+1/2007+1/2008+1/2009+1
1、(1/2+1/3+……1/1007)*(1+1/2+……1/2006)-(1+1/2+……+1/2007)*(1/2
计算:(1/2+1/3+……+1/2006)(1+1/2+1/3+……+1/2005)-
(2007-1)+(2006-2)+(2005-3)+……+(1005-1003)
(1/2008-1)(1/2007-1)(1/2006-1)…(1/3-1)(1/2-1)
1.计算(1/2006-1)(1/2005-1)(1/2004-1)…(1/2-1) ( / 分数线)
计算:(1/2+1/3+1/4+…+1//2006)(1+1/2+1/3+…+1/2005)-(1+1/2+1/3+1/
巧算1+2+3+4+.+2005+2006+2007+2008=?