1/1x5+1/5x9+.+1/2005x2009
1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+......1/2008x2009
2x5/1+5x8/1+8x11/1+.2006x2009/1+2009x2012/1 用裂项法计算
1/1x2+1/2x3+1/3x4+1/4x5+```````+1/2008x2009=?
1/1x3+1/3x5+1/5x7+1/7x9+1/9x11=?
2/1x3+2/3X5+2/5x7=2/7x9+2/9x11
1/2x5+1/5x8+1/8x11+…………+1/2003x2006+1/2006x2009 = 这是我儿子的小学作业
计算:1/1x3+1/3x5+1/5x7+1/7x9+……+1/2011x2013
1、1x5分之1+5x9分之1+9x13分之1+……+97x101分之一是多少?
1X3分之一+3X5分之一+5X7分之一+7X9分之一加到2009X2011分之一怎么算,
1+2X3+4X5+6X7+8X9=303
1x5+2x5+3x5+4x5+5x5… 麻烦给我一个公式.
急求高手解答1/1x2+1/2x3+1/3x4+1/4x5+.+1/2007x2008+1/2008x2009帮忙列出每