1/1*3+1/3*5+1/5*7+1/7*9+.+1/2003*2005
问题描述：
1/1*3+1/3*5+1/5*7+1/7*9+.+1/2003*2005
答
1/1*3+1/3*5+1/5*7+1/7*9+......+1/2003*2005
=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
答
1/1*3+1/3*5+1/5*7+1/7*9+......+1/2003*2005=1002/2005
答
等于1002/2005
答
1002/2005
答
非常简单的一道题目,
原式=1/2*(1-1/3+1/3-1/5+1/5-1/7+……+1/2003-1/2005)
=1/2*(1-1/2005)
=1002/2005