(+1)+(-2)+(+3)+(-4)+.+(+2011)+(-2012)用简便方法计算_数学解答

(+1)+(-2)+(+3)+(-4)+.+(+2011)+(-2012)用简便方法计算

人气：486 ℃　时间：2019-10-23 11:33:36

解答

(+1)+(-2)+(+3)+(-4)+.+(+2011)+(-2012)
=[ (+1)+(-2)]+[(+3)+(-4)]+.+[(+2011)+(-2012)]
=-1 + ...(-1)
= - 2012/2 = -1006