1/(1x4)+1/(4x7)+1/(7x10)+...+1/(91x94)

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/11/06 09:28:32

1/1X4 = （1/1 - 1/4）/3
1/4X7 = (1/4 - 1/7)/3
...
1/91x94 = (1/91 - 1/94)/3
1/1X4+1/4X7+1/7X10+.+1/91x94
=(1/1-1/4 + 1/4 - 1/7 + ...+ 1/91 - 1/94)x1/3
=(1-1/94)/3
=31/94

1/(1x4)+1/(4x7)+1/(7x10)+...+1/(91x94) 100x( 3/1x4 + 3/4x7 +3/7x10 +.3/97x100)=?注：1x4、4x7、7x10等均为分母计算1/1x4+1/4x7+1/7x10+.+1/2002x2005+1/2005x2008 1/1x4+1/4x7+1/7x10+1/10x13+1/13X16 简便计算1/1x4+1/4x7+1/7x10+***+1/2007x2010 1/1x4+1/4x7+1/7x10+……+1/2005x2008 1/1X4+1/4X7+1/7X10+...+1/100X103= 1/1x4+1/4x7+1/7x10+……+1/97x100 1/1X4+1/4X7+1/7X10+.+1/2002X2005=? 1X4/1+4X7/1+7X10/1+…+2005X2008/1=? 1/1x4 +1/4x7+1/7x10+.+1/100x103 急用啊小学分数题：1/1x4+1/4x7+1/7x10+.+1/97x100