1x2/1+2x3/1+3x4/1+…+2008x2009/1=?
3个回答
1x2/1+2x3/1+3x4/1+…+2008x2009/1
=1-1/2+1/2-1/3+1/3-1/4+...+1/2008-1/2009
=1-1/2009
=2008/2009;
相关问题
1/2008X2009 X(1X2+2X3+3X4+.+2008X2009) 求步骤!
1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+......1/2008x2009
(x-2008)方-(2008-x)(2009-x)=1 (2x+5)(3x-1)-(2x+3)(3x-1)
急求高手解答1/1x2+1/2x3+1/3x4+1/4x5+.+1/2007x2008+1/2008x2009帮忙列出每
(1-2)x(2-3)x(3-4)x(4-5)x.x(2007-2008)x(2008-2009)
(-1x1/2)+(-1/2x1/3)+(-1/3x1/4)+.+(-1/2007x1/2008)+(-1/2008X1
(-1x1/2)+(-1/2x1/3)+(-1/3x1/4)+.+(-1/2007x1/2008)+(-1/2008X1
1/1x2+1/2x3+1/3x4+.1/2007x2008
1/1x2+1/2x3+1/3x4+.1/2009x2010
1/1x2+1/2x3+1/3x4+1/4x5+...+1/2009x2010