(1-1/2009+1/2010+1/2011) ×(1/2009+1/2010+1/2011+1/2012)-(1+1
(1-1/2009+1/2010+1/2011) ×(1/2009+1/2010+1/2011+1/2012)-(1+1
|1/2012-1/2011|+|1/2011-1/2010|+|1/2010-1/2009|-|1/2009-1/20
计算:(1/2012-1)×(1/2011-1)×(1/2010-1)×(1/2009-1)×...×(1/2011-1
2009×2010-1分之2009+2008×2010+2010×2011-1分之2010+2009×2011+2011
|1/2009-1/2010|+|1/2010-1/2011|+|1/2011-1/2012|
(2012/1-1)*(2011/1-1)*(2010/1-1)*(2009/1-1)*(2008/1-1)*```*(
计算:(1/2+2009/2010+2010/2011)*(2009/2010+2010/2011+2011/2012)
(1/2011*1/2010*1/2009*...1/3*1/2*1)∧2011*(2011*2010*2009*...
2009÷2009 2009/2010+1/2011
2009÷2009 2009/2010--1/2011
|1/2011-1/2010|+|1/2011-1/2009|+|1/2009-1/2008|+...+|1/3-1/2
计算|1/2011-1/2010|+|1/2010-1/2009|+|1/2009-1/2008|+...+|1/2-1