|1/2009-1/2010|+|1/2010-1/2011|+|1/2011-1/2012|
(1-1/2009+1/2010+1/2011) ×(1/2009+1/2010+1/2011+1/2012)-(1+1
|1/2009-1/2010|+|1/2010-1/2011|+|1/2011-1/2012|
2012*2011-2011*2010+2010*2009-...+2*1
根号下2009*2010*2011*2012+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*...
计算:|1/2012-1/2011|+|1/2011-1/2010|+|1/2010-1/2009||+…+|1/3-1
|1/2013-1/2012|+ |1/2012-1/2011|+|1/2011-1/2010|-|1/2010-1/2
2011*2012-1分之2011+2012*2010
计算:(1/2012-1)×(1/2011-1)×(1/2010-1)×(1/2009-1)×...×(1/2011-1
解方程1/2010(x+2009)+1/2012(x+2011)=3-1/2011(x+2010)
(2012+1/2011)/(2011+1/2012)+(2010+1/2011)/(2011+1/2010)的简便方法