(1\2012-1)(1\2011-1)(1\2010-1)...(1\3-1)(1\2-1)=?
(1\2012-1)(1\2011-1)(1\2010-1)...(1\3-1)(1\2-1)=?
(1/2012-1)(1/2011-1)(1/2010-1)...(1/3-1)(1/2-1)咋算
计算:(1/2-1)(1/3-1)(1/4-1)...(1/2010-1)(1/2011-1)(1/2012-1)
|1/2013-1/2012|+ |1/2012-1/2011|+|1/2011-1/2010|-|1/2010-1/2
(2012分之1-1)(2011分之1-1)(2010分之1-1) ...(3分之1-1) (2分之1-1)
(2013/1-1)(2012/1-1)(2011/1-1).(3/1-1)(2/1-1)
(2011/1-1)(2010/1-1)(2009/1-1)…(3/1-1)(2/1-1)
1/1×2+1/2×3+1/3×4+…+1/2010×2011+1/2012×2013
|1/2011-1/2010|-|1/2012-1/2010|+|1/2012-1/2011|=?
(1/2012-1)*(1/2011-1)*(1/2010-1)*⋯*(1/1000-1)=
(1+1/2+1/3+.+1/2010)×(1/2+1/3+.+1/2011)-(1+1/2+1/3+.+1/2011)
|1/2011-1/2010|+|1/2011-1/2009|+|1/2009-1/2008|+...+|1/3-1/2