1/2008X2009 X(1X2+2X3+3X4+.+2008X2009) 求步骤!
1个回答
括号里=(1的平方+2平方+...+2008平方)+(1+2+...+2008)
=2008*2009*4017/6 +2008*2009/2
结果=4017/6 + 1/2 = 670
相关问题
(1-2)x(2-3)x(3-4)x(4-5)x.x(2007-2008)x(2008-2009)
2008+2007x2009/2008x2009-1+2009+2008x2010/2009x2010-1+2010+2
(x-2008)方-(2008-x)(2009-x)=1 (2x+5)(3x-1)-(2x+3)(3x-1)
x/1×2+x/2×3+x/3×4+……x/2008×2009=2008.求x的值.
1x2/1+2x3/1+3x4/1+…+2008x2009/1=?
解方程(x/1×2)+(x/2×3)+(x/3×4)+ … +(x/2008×2009)=2008
方程[x/1×2+x2×3+…+x2008×2009=2008
急求高手解答1/1x2+1/2x3+1/3x4+1/4x5+.+1/2007x2008+1/2008x2009帮忙列出每
已知S=1X2X3+2X3X4+3X4X5+……+2007X2008X2009,求出4XS/(2007X2008X200
2010×2009-2009x2008+2008x2007-2007x2006+.+2x1