-（1/3）^2009 -(1/3)^2008
=-[ (1/3)^2009 + (1/3)^2008 ]
= - [ (1/3)^2008 * 1/3 + (1/3)^2008]
=-[ (1/3)^2008 + 4/3]
= -4/3 -(1/3)^2008