1/2+(1/4+3/4)+(1/6+3/6+5/6)+.+(1/2010+3/2010+.+2009/2010)等于几啊?急!

Question

1/2+(1/4+3/4)+(1/6+3/6+5/6)+.+(1/2010+3/2010+.+2009/2010)等于几啊?急!

Answer 1

依次为0.5,1.0,1.5,2.0,2.5... ...,.502.5求和,故为(0.5+1.0+...,...+502.5=(1.0+2.0+...,...1005.0)/2=(1.0+1005.0)*1005/4=252757.5.作答完毕,谢谢!