1 - 2 + 3 - 4 +...+ 2007 - 2008 + 2009 - 2010
= (1 - 2) + (3 - 4) +...+ (2007 - 2008) + (2009 - 2010)
= (-1)× 1005
= -1005
-1x2010\2=-1005
答案是:-1005
1-2+3-4+……+2007-2008+2009-2010
=(1-2)+(3-4)+……+(2007-2008)+(2009-2010) 1050组
=-1*1050
=-1050
=(1-2)+(3-4)+……+(2009-2010)=-1*2010/2=-1005