(-2) +4+ (-6)+8+…+(-2006)+2008+(-2010)+2012等于多少

问题描述:

(-2) +4+ (-6)+8+…+(-2006)+2008+(-2010)+2012等于多少

(-2) +4=2,(-6)+8=2············在这组数*有503个加起来等于2的组合,所以原式=503×2=1006

=2x[(2-1)+(4-3)+...+(1006-1005)]
=2x(1+1+...+1)
=2x503
=1006

—2008

2*504=1008

(-2) +4+ (-6)+8+…+(-2006)+2008+(-2010)+2012
=(4-2) + (8-6)+…+(2008-2006)+(2012-2010)
=1006 *2
=2012