1/3*1+1/5*3+1/7*5+1/9*7+.1/2007*2005
问题描述:
1/3*1+1/5*3+1/7*5+1/9*7+.1/2007*2005
请各位帮我做下
答
原式=(1/1-1/3+1/3-1/5+1/5-1/7+1/7-1/9+……+1/2005-1/2007)/2
=(1-1/2007)/2
=1003/2007