1/3*5+1/5*7+1/7*9+1/9*11+……+1/2003*2005
问题描述：
1/3*5+1/5*7+1/7*9+1/9*11+……+1/2003*2005
答
1/3*5+1/5*7+1/7*9+1/9*11+……+1/2003*2005
=1/2*(1/3-1/5+1/5-1/7+1/7-1/9+-----+1/2003-1/2005)
=1/2*(1/3-1/2005)
=1001/6015