1/1x2+1/3x5+1/5x7+........+1/2003x2005 具体方法

Question

如题所述

Answer 1

1/1x3+1/3x5+1/5x7+........+1/2003x2005
=1/2(1-1/3)+1/2(1/3-1/5)+1/2(1/5-1/7)+.....+1/2(1/2003-1/2005)
=1/2(1-1/3+1/3-1/5+1/5-1/7+....+1/2003-1/2005)
=1/2(1-1/2005)
=1002/2005

按你原输入：
1/1x2+1/3x5+1/5x7+........+1/2003x2005
=1/2+1/2(1/3-1/2005)
=1/2+1001/6015
=(6015+2002)/12030 =8017/12030本回答被提问者采纳

Answer 2

1/1x2+1/3x5+1/5x7+........+1/2003x2005
=1/2+(1/2)(1/3-1/5)+(1/2)(1/5-1/7)+…………+(1/2)(1/2003-1/2005)
=1/2* [1+1/3-1/5+1/5-1/7+………………+1/2003-1/2005]
=1/2 *(1+1/3-1/2005)
=1/2 * (4/3-1/2005)
=2/3-1/5000
=10000/15000-3/15000
=9997/15000