1/1x2+1/2x3+1/3x4+L+1/2004x2005 怎么算?
问题描述:
1/1x2+1/2x3+1/3x4+L+1/2004x2005 怎么算?
答
1/1x2+1/2x3+1/3x4+L+1/2004x2005
=1-1/2+1/2-1/3+1/3-1/4+……+1/2004-1/2005
=1-1/2005
=2004/2005
答
我的小清新呢v,
1/1×2+1/2×3+1/3×4+.+1/2004×2005
=1-1/2+1/2-1/3+1/3-1/4+.+1/2004-1/2005
=1-1/2005
=2004/2005