简便计算:★[1+(-1/2)]+[1/2+(-1/3)]+[1/3+(-1/4)]+……+[1/2012+(-1/2013)]
问题描述:
简便计算:★[1+(-1/2)]+[1/2+(-1/3)]+[1/3+(-1/4)]+……+[1/2012+(-1/2013)]
答
解
[1+(-1/2)]+[1/2+(-1/3)]+[1/3+(-1/4)]+……+[1/2012+(-1/2013)]
=1-1/2+1/2-1/3+1/3+……+1/2012-1/2013——内部抵消
=1-1/2013
=2012/2013