(+1)+(-2)+(+3)+(-4)+.+(+2007)+(-2008)+(+2009)+(-2010)+(+2011)=_数学解答

(+1)+(-2)+(+3)+(-4)+.+(+2007)+(-2008)+(+2009)+(-2010)+(+2011)=

人气：310 ℃　时间：2020-03-21 19:14:25

解答

原式 = (1 - 2) + (3 - 4) + . + (2007 - 2008) + (2009 - 2010) + 2011
= (-1) + (-1) + . + (-1) + (-1) + 2011
= (-1) × 1005 + 2011
= -1005 + 2011
= 1006